I'm surprised, The most likely outcome of the situation could of been you becoming the scammer. By no means am I am accusing you of anything however once he sent the bitcoins you could easily charge back the payment and have both the money and bitcoins.
But to answer your question, yes you can cancel the transaction and receive all your money back providing of course you did not send the money to him as a gift, that often causes problems.
Yes, I can imagine you would suspect about me. I learnt a lesson yesterday, and now I wouldn't trust anyone.
BTW, I didn't send the money to him as a gift. He made an invoice with notes saying that I was not allowed to dispute the transaction, blah,blah. What would be the way to cancel the transaction? I have started both a dispute and a no-authorized payment. But none of them seem to return me the money.
And really, for everyone out there, at least google the guy's email address before making a transaction with someone! I always did it, but not this time.
Easy mistake to make, I've delved into things before without doing my research, its just one of them things you learn from experience.
His note on the invoice does not count for nothing by the way so try not to worry to much about that.
Here is something I copied from paypal
Step 1 - Identify issue
Most disputes are the result of simple misunderstandings. It's best to initiate communication with the seller as soon as you recognise a potential problem.
You can open a dispute in the Resolution Centre within 45 calendar days of payment. By opening a dispute, you are able to communicate directly with your seller to work out a problem transaction.
If you and your seller are unable to agree on a solution, you must escalate the dispute to a PayPal claim within 20 calendar days of the date the dispute was opened. By escalating to a claim, you would be asking PayPal to review the case and decide the outcome.
Step 1 - Open dispute right away
You can open a disputeA buyer asks for a seller's help in resolving an issue with a transaction. in the Resolution CentreLocated in My Account, the PayPal resource for resolving issues between buyers and sellers. to contact a seller directly and resolveA buyer and seller come to an agreement and close the case, or PayPal comes to a decision and closes the case. a problematic transaction. You have 45 days from the payment date to open a dispute. Common reasons for opening a dispute include:
You paid for an item but haven't received it and the seller is uncooperative or nonresponsive.
You received an item that was significantly different from how it was described.
Click the Report a Problem button in the Resolution Centre to open a dispute. Then, provide more information about the issue and post a message to the seller.
Transactions older than 45 days cannot be disputed but should still be reported. PayPal tracks seller performance trends in the event we need to take action to protect other buyers.
Step 2 - Negotiate to resolve dispute
You and the seller have 20 days to resolve the dispute or escalate it to a PayPal claimA buyer or seller asks PayPal to review a dispute and decide the outcome..
The seller reviews your message and replies in the Resolution Centre. This is your opportunity to communicate directly and resolve the issue by exchanging message posts. Communicate clearly and include suggestions about how to resolve the issue, such as through a full or partial refund.
PayPal can view all posted messages in case the dispute is escalated to a claim.
We place a holdRestricting the funds associated with a dispute so they cannot be withdrawn from a buyer’s or seller's PayPal account. on all funds related to the transaction until the dispute is resolved or closed.
Step 3 - Close the dispute or escalate to a claim
You can closeTo end a dispute or claim. A closed dispute cannot be reopened or escalated to a claim. We automatically close disputes after 20 days unless they have been escalated to a PayPal claim. a dispute if you and the seller reach an agreement.
Otherwise, you can escalate the dispute to a PayPal claim within 20 days of opening the dispute. You must wait seven days to allow for postage before escalating a dispute to a PayPal claim for an item not received. We automatically close disputes after 20 days.
Wait until you are 100% satisfied with the resolution before closing a dispute. A closed dispute cannot be reopened or escalated to a PayPal claim.
Select the open dispute in the Resolution Centre and click the desired action at the bottom of the dispute details screen to close or escalate a dispute.
We require more information from you when you escalate a dispute to a PayPal claim.
Step 4 - We investigate and resolve the claim
By escalating a dispute to a claim, you are asking PayPal to review it and decide the outcome.
We try to resolve cases within 30 days, but complex cases may take longer to investigate, deliver a final decision, release any funds and close the case.
You and the seller may be subject to specific deadlines for new information. We use the messages exchanged in the Resolution Centre, along with other details, to determine the outcome.
You can track the progress of your claim and respond to requests for information in the Resolution Centre.
We notify you when we come to a final decisionPayPal's decision resolving and closing the case..
It will take time however you will get your money back and the other idiot will have his paypal account limited.