It sounds like you may have bent the rim not just messed up the tensioning. I would take it to a bike shop to see what they would do but don't let them do anything unless it just needs to be trued. Its probably easier just to let them do that because thats probably on of the hardest things to do (maintance wise) to your bike. And don't let them give you a new rim cus my friend did that and the bike shop was lazy and gave him a new wheel and charged him like 160 for something that could have been fixed for 50 bucks.