Symptoms.. need help!

So, I've been having these symptoms lately. They include the following:

Low grade fever (99.2-99.8)

Nausea/watery mouth

Heartburn/Indigestion

Constipation (when I can poop it's only little rabbit turds. Tmi. Sorry.)

Low abdominal cramping (not nearly as bad as menstrual cramps, but noticeable and kind of annoying)

Lower back aches (I do alot sometimes, so this isn't always unusual for me)

Headaches (again, not too unusual, but I don't usually get them this often either)

Sore/tingly breasts/nippers

Itchy Skin

Dizziness

Shortness of Breath

Mood swings (my bf is currently trying to avoid me bc I bitched about him takin my car to put gas in, even though it's freezing outside and I should have thanked him)

That's the most of them. I'm just unsure of what's going on here. I took 2 hpt and both were negative. I had my period in end of January, but it was very light except for 1 day it was a bit heavier. I didn't really think about a chance of pregnancy because I've recently found out I have endometriosis. The tests I took were yesterday and monday.

If I were pregnant, wouldn't it show up now??

Health history... I have hypothyroidism, endometriosis, pernicious anemia, presyncope. I know the thyroid issue can throw things off, but I didn't think by this much. I was going to wait a couple days and take another test, but I just would have thought if I was pregnant, it'd have shown up by now.

Any thoughts?? ... thanks for reading!