We all have days like that, it is so frustrating! I sewed a unit in a block wrong on Wednesday. Ripped it out and put it back in. WRONG. Thankfully, the 3rd time was the charm, but I was done for the day at that point.
Are you sewing the binding on with a regular sewing machine? If that's the case, snarls on the bottom are almost always caused by a threading problem on the top. Clip the thread at the spool, pull it out through the needle, and rethread, making sure that your presser foot is up when threading.
If you are putting it on with a LA, I don't have any suggestions other than to say that I hope things go more smoothly today!