Soooo frustrated and confused! 😞

I had been nauseous for about 2 weeks prior to my period and thought maybe I was pregnant.  Well af showed up and I thought that would be the end of it.  Af was very heavy (as usual). We here I am 2 weeks past af and still nauseous. Took 3 tests that have all been negative and yet the nausea still persists (no tender breasts).  The nausea is mild and is relieved when I eat but quickly returns.  At least if I got a bfp I wouldn't mind but all of these bfn's with this nausea make me frustrated.  The past 2 days I've also been experiencing bouts of anger. This usually happens a few days before af, but that's still a week and a half away.  I'm so confused and upset 😞. Has anyone else ever experienced this?