So the lake I fish is small, has one tiny creek running into it but it's blocked with a dam. It was used as a water project to prevent the creek overflowing. That's the only real water flow but it's usually closed so my question is where would the bass go in the fall? Usually I see how the bass go to the backs of creeks in a body of water but this has none. So would they just go shallow then? Or stay where they are

It would depend a lot on the main forage of the lake.  The reason the fish go up the creek arms on the big inpoundments is because that's where the baitfish go.  That's what they'll do in most any lake unless there is an abundance of varied forage.  I know it's a very generic type of answer, but there are a lot of other factors that influence where they may be.