How to get rid of thumb pain on the right?

Try few things, 1st. Localized, unilateral joint/muscle pain has a variety of causes, most likely some kind of trauma, repeated movements leading to mm strain, early osteoarthritis--old bone or degenerative arthrittis-- at base of thumb is very often the joint first affected. Rest it (play piano, use computer or texting a lot?), ice it, perhaps anti-inflammatory (advil, alleve), for a week. If persists, check w doc.