Dear juliann94
There are a couple of checks you can do, but if equipment is faulty, you require the services of a handyman or a real professional repairman.
Check the thermostat : is it set properly?
Check the compressor : is it running and getting hot?
If running but not hot you have a freon leak.
If not running the compressor could be faulty or another electrical fault may cause the problem.
Also possible : can the heated gas cool down sufficiently? Sometimes dust covers and/or blocks free airflow over the radiator panel. Is the fan running ? (if you have a split level unit).
Open the unit(s) and check what is going on, and what is not ...
;)