If the tooth pains only while chewing and is otherwise symptomless , you can probably get it reduced a little bit so that the tooth gets out of occlusion and the healing happens faster.
Actually, it is difficult to comment on your case without any X-ray . Visit a dentist to get a proper diagnosis with a clinical examination to rule out any tooth fracture as well as an X-ray of the treated tooth.
Next Steps
Visit a dentist . Get Xray and clinical examination done to rule out any tooth fractures. If the RC filling is adequate, maybe the tooth needs to be out of occlusion for some time to promote healing.
If the tooth needs re treatment, please go for it.
Health Tips
You can get your mouthguard altered to your size . Alternatively, get a customized mouthguard to eliminate pressure on gums .Habitual prolonged clenching may lead to TMJ problems. So, do not ignore.