strange hospital visit

Mrs P • Wife & mummy to a 10 month old. 👼🏼 11th of Dec 2017 💔👼🏼
I'm at the hospital twice a week now for monitoring. I got there an hour early so had some lunch and sat in the cafe before I went for my appointment. Got taken and was on the CTG monitor when I started to get breathless. The midwife kept asking if I was ok I said I was fine and it will pass. She popped the blood pressure monitor on and my BP was really low and my heart rate was 133. Told her I felt like I was having palpitations. By the time a doctor came to see me (was a good 45 mins) it had calmed down. They done an ECG and it was normal. Anyone else experienced this? I have every sign of pre eclampsia except the blood pressure of course! Even now I'm starting to feel light headed. I eat PLENTY lol feel like I've left the hospital with more questions than answers.