While masturbating I notice small pimple like bump (underskin) next to maybe two other bumps that feel amost connected on the underside left of penis where pinky would be if right hand is being used. Its lots of veins there where skin loosen. Cause???

Without examining. the area in question it will be impossible to provide you with a diagnosis or reason for your findings. You will need to see health care provider for an evaluation. It is probably normal for you but I am sure you don't want to take the chance it could be something more serious.