A/C blowing warm and cold

I just recharged my A/C. It was working okay, but after a couple of days it was cycling between hot and cold again when blowing. It check to see if there was still R134 in the system and it is still full since recharging it. The compressor seems to stay on all the time, I rarely see it turn off. However, the other day I was watching it and I saw the compressor turn off for three seconds, then on again for three seconds, then off again and it kept doing that. While it was doing that the air was blowing hot. When the compressor is constantly running, the air is cold. It seems there may be something wrong. Any ideas?