Lots of diseases will give you a fever.
If it was so loose that the head was unprotected it would have fallen off. It is unclear from your description exactly what happened and where when you say "resting next to". Please provide more description because it sounds like you withdrew and the condom was next to your penis after that. If it was so loose that it fell off during intercourse you would be soft and not penetrating.
A condom slipping does not lead to HIV. Only the head of the penis needs to be covered. You don't need to test as you had no risk. The only risks are unprotected (head of penis) vaginal or anal sex or sharing IV drug needles. For info purposes, while a 4th generation duo test is very unlikely to change at 22 days, the test is not considered conclusive until 28 and beyond. Symptoms are NEVER used to diagnose HIV.
"This is clear to me, that penis head must be involved." Actually the urethra is where the virus would have to travel down to infect you. It can't penetrate into the head especially just from touching.
sb
.... can't get hiv from oral sex and touching it.