I have 2 extra ribs & about 2 months ago they caused pain in my right arm & numb thumb & finger. I don't get much pain but still have numbness! Thorts?

Be seen. I would certainly recommend you be seen and followed. Certainly one possibility in light of what you said is thoracic outlet syndrome, in which an "extra" rib can cause nerve and vascular compression. There are other possibilities as well.