I've been on a program since early 2012 to help build my credit. The last payment is tomorrow 11/1.  Will this boost my score some, or make it drop? I'm at 595 now (), was at 621 on 10/6 and still trying to figure out why it dropped to 595 on 10/24.  

I didn't do anything differently or even use my credit cards...also was not late on a payment.