I have just finished antibiotics for a toothache and 2 days later it came back. I don't have access to dental right now, can I take more antibiotics?

Toothache. If your tooth pain isn't just from an infection but from an inflamed exposed nerve root. Antibiotics won't cure the issue and it's common that the pain would return.
See a dentist. Antibiotics can suppress a dental abscess for a 7-10 day period but will not cure it. Continued use of antibiotic can suppress susceptible bacteria but allow restitant bacteria to flourish & make future treatment very difficult & less successful. The only cure for infected dental pulp is root canal therapy or extraction. If it is only deep decay or severe root sensitivity, antibiotics don't work.
Possibly. Antibiotics aren't meant to cure infections. They only help your body turn the tide against the nasty buggers. Antibiotics really are meant for short term use. I strongly advise you to seek dental care - even if it means going to the county facilities. It's rare but people have died from dental infections.
Not successfully. The infection is either unmanageable by antibiotics and requires definitive treatment, or the antibiotic is not effective against the offending bacteria. Doing the same thing again will not resolve the problem.
Not recommended. If you have a dental abcess (infection) causing the ache, chances are that more antibiotics may help in the short term but cause larger problems in the long run. The nerve of the tooth sounds like it is still partially alive and is most likely the culprit.
Yes, but… Longer one is on antibiotics, the greater the risk for resistant bacteria to develop & greater risk of c. Difficile-associated diarrhea. Make an appointment with a dentist asap; you can work out a payment arrangement. Check for dental school or clinic in area, that may use sliding scale payment based on one's income.
Not sure. If you didn't take the antibiotics long enough, you would not have allowed them to eliminate the infection. Only your dentist can tell you if you are on the correct antibiotic. Tooth is only going to get worse. Bite the bullet and get into the dentist. Work out a payment plan if you have to. Not having dental insurance is no excuse for letting your dental health suffer or losing teeth.
Get it treated. If you are having a toothache that is relieved by antibiotics and then comes back after antibiotics, the tooth is likely abscessed. That means the decay extends into the pulp and there is pus draining out of the end of the tooth roots. You must have the tooth treated with a root canal or extraction. You can't walk around with a part of your body rotting and draining pus.
You shouldn't. If your first course of ab's didn't get rid of your toothache, it's probably because the infection is so far inside the tooth that the medicine can't get there. Or, it could be the wrong ab. In either case, taking more is unlikely to help. The best way to get rid of tooth pain is generally to open the tooth and clear out the infection mechanically. More of the same ab won't help you. Sorry.
Short term ok. If you don't have access to dental care right now, extending with a refill of the same antiobiotic from the same healtchare provider is usually not a problem. (they can refill over the phone) but...Rather than cover up what might be a residual problem, or a secondary problem, it is best to return to your treating dentist to re-check the area as soon as you can.