Well, AWA score 3 or less is not extremely positive - it will make adcoms think you've used essay editing services
First, wait for the score - may happen that you have a 4, which is enough to forget about it.
Second, try to understand what was the reason of your poor performance. Was it just bad luck? Or nerve? Or typing speed? Or lack of sleep? Etc etc etc...
After that, think what is your chance of doing much better next time. If it was some fatal coincidence - you could be quite able to go for a 5 or 6; if not, and you realize that AWA's just too tough for you now - then maybe you shouldn't waste time, effort and cash for useless re-testing.