STD??

I have:

vaginal itching

weird grey but clumpy vaginal discharge, cloudy

sometimes soreness when sitting

itchy butt

got tested for yeast, BV, and trich. all negative

took flagyl and fluconazole, did not work

I heard chlamydia and gonnorhea can cause anal itching so it would make sense... I also had a full body rash back in august so there’s possibility of syphilis as well. thoughts?? what were your STD symptoms if you had any??