You were correct about what is a common normal number, for bp (120 over 80)
@Ruthanne
The much higher number that you are getting is too high.
But there are 2 possibilities. One is whether or not your monitor is giving you an accurate number or not. It could give you an inaccurate number, Either because it might not be working, or you might not be taking it correctly.
The other is, what were you doing at the time? You should sit for a few minutes and relax, before taking it, and follow the instructions carefully. The bp number can go up and down many times per day, in response to your activity level. That fluctuation is normal. It goes up to help you, if you are exercising, etc.... It also goes up, when you are nervous or upset or excitd, but should go back down, once you relax.
But if it stays up that high a number as you said you got , then that is too high, and you need to be checked out.
Drop salt in the meantime, as it causes bp spikes as well.