How can i tell if i have an abscess forming on one of my teeth?

the problem is that i had an extremely bad abscess already on this same tooth that has been fixed prior to it ever happening, and the dentist never helped me when i had a full blown abscess. the e.r. did more for me then the dentist did, but that was five months ago. now i woke up with the same twinge of pain that i felt in the beginning of that episode. i would rather go through labor than EVER GO THROUGH THAT AGAIN!!! when i bite down it causes pain to shoot up into the root of my tooth which is new as of a couple hours ago, and also seems to be a little looser than usual (it never fully went back to complete hardness after the abscess was treated, it was always a little loose) so i want to stop it in its tracks before i end up that bad off again.... so if anyone has ANY ADVISE please help me!!! i am a single mom with a toddler that needs me, and wont be babysat by NO ONE due to real intense separation anxiety (lately), thanks!!!