Did I just steal a library book?

It has been a while since I have requested books from the library. Recently I requested two books. While two were in the process of transit, I had got ahold of the two books by other means and repeatedly tried to cancel the requests with no luck. Well I then requested a third book and went to my local library today to pick up the books and return another. I went to the bookshelf stacked with the requested books and took the three I requested. I then walked to the return machine-thinga-maggigy and returned the two books I did not need (the requested ones I had got ahold of by other means) without checking them out, along with the other book I had to return. I then left with the third requested book without checking that out as well. After I left, I had realized I probably made a huge mistake because when I checked my check out history it had said I didn't have anything checked out and my account info showed I still had three requested books waiting for pickup. Did I technically steal library books without realizing it or meaning to? If I go to the library tomorrow and show them the return receipt for the books and the third requested book, will the problem be cleared up? Will I be fined for stolen books? I have the page they attached to requested books that tags your name and library card number. I was thinking of using that as some sort of receipt. Could i go back and fix this somehow and check out the third book I took off with? I'm really embarrassed and I realize I made a stupid mistake. Please Help.