Bitcoin-QT user here for Mac:

I went to the "Addresses" Tab and relabeled one of the addresses I had in there.

I went back to send and clicked on the address book and selected the address I just renamed thinking I was designating it to use THAT address for the SEND FROM address.

Wasn't really paying attention and shipped off a couple Bitcoins thinking it was going to the right person from that address.

Turns out I just sent it to that address.

TLDR: I sent bitcoins to an address made for sending payments (Addresses tab). So I sent it to an address that the client was going to use to send coins from.

Jesus I hope this makes sense....

How do I go about gaining access to that wallet or did I lose all of my bitcoins?

I'll tip whoever is able to help me!