There's to much tension if you can't squat ass-to-floor without weights. 
Try box-squat or bench-squat, bench should be around parallel, only with a bar. 
Your technique, as in bodycontrol, isn't right. 
Everybody should be able to squat and stand up again. 
Master in your freetime an asian sit-technique;

couldn't find a other pic.
Squat and get up again. 
A other problem could be your clothes, 
the pro's wear the stupidious short-trousers with a reason.