Bactrim Std Tests, Blood Culture, Augmentin, Gyno, Lesion

I had been taking bactrim for a week when one morning i woke up feeling achy, tired, and light-headed. I noticed a slight rash forming on my arms but didn't think much of it bc i had been on the Bactrim for a week already. Then the symptoms got wayyyyy worse. I started to form lesion like sores on my vagina, and I immediately saw a doctor to get tested for STD's. The gyno examined the area, and she said it did not look like herpes but that she would test for it just in case. She put me on augmentin bc she said I definitely had some sort of infection down there. After taking 4 doses of augmentin almost all the lesions went away. The STD tests (blood, culture, and urine) all came up negative, as I expected they would. Has anyone else had genital reactions to bactrim???? Because as of right now the doctors are unsure what caused this outbreak/infection.