U = Unconfirmed (input).
Spent = Used already in a new transaction.
A chain of unconfirmed transactions means it takes longer for the last one to confirm. If they're all your own transactions you can safe on fees if you send one transaction to multiple addresses.
No it's just one transaction which is mine, at the beginning there wasn't that U and Spent, will it take a long time than normal transaction for first confirmation?
Yeah it will take time to go through because you are spending the transaction having unconfirmed input.
If you don't want to wait for a long time then you can double spend your transaction to get your coins.
BTW i have seen that your stated transaction has been confirmed and spent.