Congrats, you dodged the bullet, and as curfewx said, you do not have HIV, any HIV test is conclusive after 3 months, and remains conclusive whenever is done after 3 months mark.
Lesson learned, never ever unprotected again with anyone outside your mutually committed 100% monogamous relationship.
A real friend of a girl is mot her boy friend but it is a condom, that protects her from the risk
You have tested conclusively negative so you were lucky. Any test after 3 months is conclusive. Symptoms aren't used to diagnose, so there is no need to study them before or now.