Hi Natalie,
That's de ja vu for me. I had exactly the same thing happen when I was around 17 weeks, and have experienced it off and on since then (i'm now 26 weeks, and it's getting a lot better). I was sitting at the time talking to my dad on the phone when it hit. I tried to change positions, even ended up lying on the floor on my lefthand side and it still got worse. I had difficulty catching my breath and started to break out in a cold sweat. I began panicking because I had trouble breathing, which I'm sure didn't help. My DH gave me some orange juice which seemed to help a little. Called the ambulance and felt fine by the time they arrived. Apparently it's caused by my low blood pressure which dropped significantly because of the bub pressing against the inferior vena cava vessel in the uterus. I was told to try and keep up my fluids, take shallow breaths, as deep breaths can accentuate the problem, and lie on your lefthand side with your legs elevated. I know it's scary honey, but it eventually becomes much easier to manage.
Hope you're ok!
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