Help. Ac problem

Hi. I recently changed my compressor and did over the system. Thing is. I noticed as of today that when i turn on my ac the rpm drops by 100 or little over and the compressor does not disengage as it should. It just keeps running until i manually turn it off. But it is blowing cold air and even colder when i drive. Now my question is. What is the problem for it to not disengage and also for it to drop the rpm????

 

May have a relay stuck or shorted or you over charged system also check pressure switch since you mentioned the 100 RPM drop I'm leaning towards overcharged

 

Oh okay bro. Thanks for the reply. I will have it checked right away and give feed back.