Out of balance

I can't seem to balance my checkbook and it's driving me crazy.  It's not like it's off much and the bank says I have more than than I do so I guess I should leave it alone but that doesn't work for me.  I was off by a mere $4.48 yesterday and now it's grown to 25.02 in my favor.  What's goin' on?!
Part of the problem might be I'm not really giving it the time to go over it properly to find the error.  It's there, I'll find it, but I look briefly then go on to do something else...like I have accounting ADD.
I've taken for granted that I can always breeze through checking the records that when I have an error I don't find immediately I put it off for later.  That seems especially true when I see there are still pending transactions on the banks side that I've already considered as paid.  I know they will be deducted soon enough so I don't count them as available anymore.  It can get confusing when I see them pending and then they aren't there anymore and then days later appear again.  I'm not sure what the companies are doing with that?!  Or those silly $1.00 pending charges I get from iTunes when I purchase music on-line.  Like they don't know what the price of the CD is even though it's posted.  So that works into the balancing formula...add the $1.00 back then subtract the 10.48 actual price.
No wonder I'm off a few bucks.  But I shouldn't be...so I need to go back and find it.
Maybe it's just an addition error...or maybe I have $25.02 more than I thought.  Either way, I can't leave it like that.  I need to go back and check.
TT