I have vibrations in my muscles/veins, sometimes so strong I think my phone is buzzing. They don't hurt but I'm still curious what they are.?

Might be low calcium. If you are having tingling numbness around your mouth or hands and feet, or muscle weakness, you should see a doctor. Otherwise, it sounds like benign muscle spasms (twitches really). A few muscle fibers are overstimulated, variously attributed to low calcium or stress/anxiety. Athletes can also have these twitches, and the exact mechanism is unclear. Dietary calcium and less stress may help.
Doctor can evaluate. Muscle twitches in a few muscle fibers can start and stop on their own. The fibers don't create enough force to cause a big movement but the twitches are annoying. Some people report vibrations, which would be faster than twitches. Muscle cells do vibrate at certain frequencies during some kinds of contractions. A pm&r (physical medicine) doctor or neurologist who does muscle testing can evaluate.