When i go to overhead press and im standing like the guy in the pic, as i push the weight up i get a shooting pain in my right hand like i can feel blood rushing up my vein (blue line) then i get a spiking pain in my hand (red lines) as the weight makes it to the top. If i ignore the pain i can get the weight up but im afraid my vein might pop if i keep doing this. I checked my pulse on both my hands when i was done and it was beating alot faster on my right hand. My hands feel fine for bench press and everything else.

Whats wrong?