Do I Have This Health Condition? Seeking Advice from Those Who Know

I have quite a few of these symptoms but I have IST

Sounds like POTS from your description. Start keeping a log of your heart rate, symptoms, what you've eaten/had to drink. A few questions, does your bp run lower than normal? Have you done the "poor man's" tilt table test? I'll include a link. Does your heart rate spike when going from laying to sitting, sitting to standing? (This is why I suggest the tilt test) Some right now things you can do. Start drinking more water and increase your salt intake. It is the first line of treatment for POTS. If you don't care for salty food, you can do electrolyte packets in water, LMNT is my favorite but you can also do liquid IV, drip drop, banana bag, etc. Also, I know that it is hard and scary but try to start being upright as much as you can. Start SMALL. Like, stand up (slowly) and walk a lap around your house once an hour. If you need to use the wall for support, that's fine. You will feel better once you get a bit more conditioned to being upright. Last, if you are feeling really horrible, there are IV infusion offices in most major cities. You can go in for saline or lactated ringers as a way to get you hydrated more quickly. If you are having GI, Neuro, or any other symptoms, you might want to read about dysautonomia. It's POTS plus other symptoms. I have hypermobile Ehlers-Danlos which originally started out as a POTS/Dysautonomia dx. My doc and I started putting pieces together to figure out what was going on with me. My dms are open for POTS questions!

Definitely sounds like POTS. I feel like this alot

I suffer from most of the symptoms you have mentioned. It does sound like you have a lot of common POTS symptoms. Does your heart rate remain high even when sitting down? My heart rate runs high most of the time, but when I stand or exert myself in any way, there is a big jump in my heart rate. Have you been evaluated by a physician yet?

Sounds like a lot of the symptoms I have, but I'm not a medical professional and the best thing is to talk to a professional.