What a day! Has this happened to anyone?

I went to the doctors for my 25 week check up. The nurse (who was new) took my blood pressure took my blood pressure and it was 140/90 - which made me panic because I never had high blood pressure before. So, my OBGYN sent me for a maternal observation over at the hospital. Well as soon as they hooked me up my blood pressure read 120/60, and then for the next two hours it stayed around 118/52. They tested my blood, and in the nurses words it came back "perfect" and both of the urine samples I gave had no traces of protein. So, tell me why my doctor is making me pee in a jug for 24 hours when all the tests came back normal? Lol. Better safe then sorry but y'all what a day!