Suggest Remedy To Ease Pain And Swelling In Left Thumb

I have pain in my left thumb. I didn't do anything to hurt it. It just started hurting lastnight now it hurts more and is red and swollen. The pain is where my finger print is and is at the bend and goes to the end of my thumb. What could this be and what should I do? Please help I am 32 weeks pregnant and not sure of its serious. It hurts bad.....