Dear client
First check there is no other signs like swelling or tingling sensation or prickling sensation ...?
If no then :
1. You must take hot water bowl and put ur thumb in that for 15 min twice a day
Otherwise u can use hot water bag
2 . Stop writing if extremely painful
3. Thumb Flexibility exercises..if necessary
Next Steps
If pain is not reliving then you must do proper physiotherapy for thumb pain
Ultrasonic therapy may b helpful for this .please follow physiotherapy protocol it's really helpful without side effects