How do i know if my tooth needs to be extracted or just filled? i cant seem to get an earlier appointment, and have no clue if the decay is so bad it cant be restored. if not now, i worry my cavity might get to that point before my appointment?

If you have no swelling or pain than that is a good sign. You should find a walk in office or clinic for exam and x-ray. Don't wait, any delay could cause more problems and more extensive as well as expensive treatment.

You personally cannot tell what treatment is needed. Don't know how far our your appointment is, but a month will not really make any difference.

You can't self diagnose. Small cavities, remove the decay/infection, put in a filling. Large cavity with diseased tooth pulp, root canal treatment/crown or extraction/implant/crown. And lots of other choices in between. We cannot diagnose you from afar. Ask your Dentist for the best treatment based on your personal diagnostic criteria.