2001 honda civic overheating?
 

2001 honda civic ex 4door i have been having problems with my car over heating for the last month sometimes not always i change the thermosta, water pump, timing belt, and radiator and was fine after that for about two weeks and i check the radiator and its not leaking and when i turn my heater on no hot air comes out its just cold air and the a/c light in the dash turns and my a/c fan turns on if i let it run for 5 minutes the temp. goes up i checked it for leaks from heater core and there nothing the coolant is coming out of the reservoir. i can any body help me.