What the helk happened?

I started out with an $82.75 balance, which was $5 more than what I was depending on.  A few days later that balance went up to $90.88 after a couple items in my Amazon inventory sold.  One of the items I sold was an item I had acquired through my mom re-paying me for a $15 purchase I made with my debit card on her behalf, the same day as the deposit that brought my account balance to $82.75.  From $90.88, the $15 purchase brings me down to $85, and I also bought a $16 book, which, I resold for $10, so, cutting the filler etc. out of the equation, that's $85 - $6 =ing $79.  My mom's b-day gifts cost'd me $27 =ing $52 from $79 and I also bought $11.75 worth of lattes from Cup & Cork and a $9 CD from Amazon, bring me down to $31.  As far as the rest of the money spent goes, here's what my bank account statement tells me:

$2.66 Redbox
$2.55 Hastings
$2.33 Hastings (again!)
$3.19 Starbucks
$0.83 Kidd's
$0.99 Amazon
------
$12.52

You'd think this means I should have a balance of $18.50 apprx, but, seriously, WHAT THE HELL HAPPENED???

In any case, my plans for August, since I have a $41 doctor bill (mostly for dentistry, which Medicaid doesn't cover), are as follows:

NO $2.66 redbox
NO $5+ Hastings purchases
NO $3+ Starbucks stuff

Between this and cutting back on the even smaller purchases ($0.83 for Kidd's, for example), I should be A-OK.