Car is Overheating now on 2001 BMW 325i

Just replace water pump and belts, NOW, my car is overheathing. Any idea, what cause this?

2 answers 1 comment
If it has a serpentine belt, make sure you installed it correctly, if it is wrong, the water pump may spin backwards, and not work correctly. Some cooling systems can get a large air pocket in them after the system has been opened, and this can cause overheating.
Thank you for your help. I check everything and it seems to be fine, but, still my car is overheathing after I use the car for a little while (10 minutes of driving)
Just found this site but just in case you are still in trouble w/ overheating, mine was the resevoir - it had a tiny crack where the coolant was leaking out.