Steadymining says I've generated 128,001 coins by solving blocks. but I only have about 7,500 in account balances. So, is the pool really far behind, am I getting screwed, or am I just much, much better off solo mining?
That's the amount of coins that were in the blocks you have solved. That total amount of blocks has been spread over all pool miners (as that's the target of a pool). If you would have been mining solo, you would have gotten that amount of blocks - However, there's no way of telling if you would have had the chance to solve those blocks on your own.
The 7500 is your fair share of the amount of coins you've earned, by dividing the total amount of shares, by your amount of shares submitted. (Simply, that's how a pool works)