It is the law of averages catching up with you, unochamps--if you go 7-2 on Saturday, statistically you are likely going to go 3-6 on Sunday (or somewhere in that neighborhood). As long as you are betting consistent units (not "laying it all out" after you get ahead or trying to make up for losses by "laying it all out" again), you can win over time.
I can't tell you how many times I've cleaned house in CFB and given it all back on NFL games because I got greedy on Sunday. Hang in there.