I know what I would do, I would break out two big hammers and work the aluminum skeg till the boat went straight and not pull and then use the other tab to fine tune it.

I would pull the prop off and check the shaft and make sure it wasn't bent, you can put an indicator on it and turn it slowly and see if it's bent.

I would also do as suggested and check the fluid in the foot and then run it and let it sit in the water for a while and then check it to make sure no water is getting in it.

If all of that was good then I would call it good, work the skeg over last and call it good.

If any of the other things didn't check out then take it to the Marina for an estimate.