my right side is sitting much lower than the left?

Probably a leak in the air leveler system on that side.

How hard would it be to fix?

All depends on the location of the leak, take it in and have it looked at, should be an easy fix with the right tools and parts.

So nothing I can fix in my self even if I'm mechanically inclined?

It has an air spring I changed mine myself there's a few videos online it's not too hard too do