Mazda protege wont accelerate over 40 mph after having clutch kit replaced

What is your question?

In 1st the car shakes extremely bad and once shifted into 2nd it tries to act normal but womt speed up over 20mph, 3rd wont accelerate past 30mph, 4th I can get it to go 40 mph. Wont go uphill or small inclines hardly the car will stall if the incline is too steep. When taking off from a stop sign or complete stop the car is extremely slow to move and sluggish almost cant cross 2 lanes of traffic when needed. Recently had a clutch kit installed when I picked it up from the mechanic is when the problem started. Before the clutch went out I didn't have this problem.

What makes this problem better or worse?

When it's hot outside or cars at running temperature

How long has your 2000 Mazda Protege had this problem?

2 weeks