What would be the symptoms

What numbers are you getting and why do you ask?

I once had a reaction to a medication that sent my BP to something like 60 over 40, but the nurse said it wasn't even readable with a regular cuff. I was sleepy and weak. Another time too, 10 minutes after a laparoscopic surgery, it dropped, I also was sleepy and weak, and I drank a small cup of orange juice, was fine in 5 minutes, and went home. I usually had a BP of 110/80.