I've had this happen once when I cut my thumb cutting glass tubes for a high school science class; I had to be semi-carried me to the nurse's office who got me

I've had this happen once when I cut my thumb cutting glass tubes for a high school science class; I had to be semi-carried me to the nurse's office who got me to drink orange juice to recover. The weirdest thing is that I'm perfectly fine getting my blood drawn for tests and watching the nurse draw the IV or swap out vials; it's just that thumb injury that cause me to go lights out