Early miscarriage?

I am making a doctors appointment as soon as I can but wondering if someone else may be able to help me in the meantime. My husband and I have been trying for baby #1 for about 6 months now. All pregnancy tests have been negative. I was having cramps a bit earlier than my expected period then they became severe quickly. I had extreme nausea, throwing up and the most severe cramps I’ve ever had (they’re usually pretty bad, this this was intolerable.) I was writhing on the floor and couldn’t walk. I was sweating and almost passed out going down the stairs to get a heating pad. I filled a hot tub and laid on the bathroom floor, got in and passed out for over an hour in the tub. I had to cancel all plans that day. I looked online for some insight because I had never experienced anything like this and read that it could’ve been an early miscarriage, but I haven’t been able to find much more info. Has anyone else experienced anything like this? Any info is greatly appreciated ❤️

Edit: I should’ve mentioned there was bleeding as well, I just assumed it was my period. Thank you all for your responses so far.