I have a 2010 Giant Suede 21 speed bike. I took it in about 2 weeks ago to my LBS for a tune up. I hadn't ridden the bike much at all this year (or honestly last year of no fault of the bike) before taking it in for the tune up. I did notice that when I was going slow and up a hill it did "skip" a bit under pressure in second chain ring and fourth gear only. I hadn't noticed any other issues.
So I get the bike back and wasn't able to take it out for a spin for a few days. When I did to my shock, the chain skipped under normal cadence and in many gears and went into other gears as well. I have 2 other bikes I enjoy riding and havent been very motivated to get it fixed. I am wondering what I should do? Also from reading about the symptoms I at some point may have stretched the chain??? A side question though is why getting a tune up would make this worse?