I'll preface this with saying that I'm relatively new to bike repair but I'll try my best to explain things.
Right now I'm trying to adjust my rear derailleur. A few weeks ago my bike took a bit of a fall but I'm pretty sure that I bent the part that hangs lower and keeps the tension. I don't think it's that bad as it hasn't dug into the spokes yet but shifting gears has be interesting ever since. I've got it mostly fine tuned but the problem still exists of the derailleur completely skipping a gear when I shift. Right now it seems to completely skip over the third (of six) but anything within the third to fifth range is pretty shady. I've adjusted the limit stops to stop the hanger from rubbing up against the spokes as best I could (so far it has stopped) and tightened the adjustment barrel to make the shifts a little bit smoother. Regardless of what I do it always seems to skip over this gear.
Any ideas on what could be causing this and/or how to fix it? I'd much rather not have not have to take it into a shop since I don't have much money to spend right now (starving college student, etc).