Problems With Chevy Aveo 5 Speed Manual?

I bought a 2007 used Chevy Aveo 5 hatchback 3 months ago. It has the 5 speed manual transmission. I've driven a standard before (Jeep), but after 3 months still can't seem to get the feel of it to drive it smoothly. It just seems rough and awkward at times to drive. It jerks a lot stopping and starting, frequent stalls, shifting is not smooth, seems to be a lot of vibration in the clutch petal at times, and when downshifting from 5 or 4 to 2 or 1 (such as coming up to a stop light) there is a lot of vibration and a grinding feel in the shifter. I know how to use the clutch but it just doesn't seem smooth. Do I just need more practice or is there maybe something wrong with the car?