bump in inside of hand on thumb

A day ago i noticed a feeling in my thumb like a had a splinter at certain times but there was nuthing that i could see there. Now today theres a very small bump there n i have no idea what it is , it's sore and a little swollen and red but the actual bumb is white I thought maybe it was a wart . but nothing that i looked up described what i have. i cleaned it and ried o poke it open to clean clear liquid comes out but its still stays there. It is very annoying and painful especially on the right hand that i use the most i feel as though i cant use my thumb for anything. will sumbdy tell me what this could be. thank u