So I had unprotected sex with someone 6 weeks ago. The day after I got sick and I've been sick ever since and all the symptoms have gone away except for headache and stomach pain and fatigue. I got the hiv 4th gen test done at 30 days after I had unprotected sex and it was negative and I've asked the person and they say they don't have it but they had 4 partners before me which really scared me and I had contact with someone else and we contacted saliva and they got sick too. The day after we exchanged salvia they got nausea and flu like symptoms the next day. Could this be hiv even tho my test came out negative. I got sick the day after sex so idk if that's a sign. What could this be? Thanks for the help.