Hard shifting after tune installed

I just had a tune put in my Silverado 2500hd 6.0, now it has a hard shift when it kicks down from higher to lower gears, I can feel it in the floor. Shifts fine when accelerating hard. Not a firm shift just a clunk when it changes gears under moderate acceleration. It does not seem right. Feels like it is bad for my transmission, I do not like it at all. It was smooth as silk before custom tune. Also feels like I gained some power at high rpm's, but lost power at low rpm's. Is this just a bad tune up? Is this bad for my transmission? They advanced my stock timing from seven degrees to seventeen degrees and added more fuel, they did not say anything about adjusting TCM? Any idea what may be going on? Any advice would be greatly appreciated, I am going to take it back in tomorrow.