Partial Facial/Mouth Numbness

For the past few months I’ve been experiencing reoccurring numbness in the right corner of my mouth, so far a reason hasn’t been found yet. It’s usually only in that spot and it’ll come and go. Some days it’ll last for hours and be very uncomfortable and others it’ll be brief frequent moments. Also sometimes I’ll get painful, pulling feelings on that side of my face or cold pins and needles. Those are rare compared to the daily numbness.
In the Summer I had dental fillings and I had lasting numbness on the right side for maybe 2 weeks. My dentist said it was nerve irritation and would go away, and it did! That was July and until December I didn’t have any problems. My fillings healed fine, I have no sign of infection or abscess.
So far all my PCP could tell me is that I seem to be having numb chin syndrome. I did a blood test for B-12 levels and they were perfect. Overall I’ve felt very warn down, new muscle pains in my arms and legs, fatigued. Now I’m waiting on an MRI.
I haven’t seen anything online that matches how I’ve been feeling and wasn’t too sure where to put this post. My PCP said we’re doing the MRI to check for “tumors or lesions” and that’s been insanely freaky to think about. So if anyone has any insight that’d be greatly appreciated while I wait for my scan!