please elaborate ur question.
When was the RCT done?
If the pain
persist.Please visit the same dentist
immediately. .Dont take antibiotics by urself.It is not going to help U in long terms.
If the pain is due to improper rct.U have to undergo a re-RCT.
Without seeing a pt in person we are not supposed to prescribe any medications.So pls visit ur dentist immediately.