I'm glad you posted because it can be so stressful facing these questions. It sounds like you are nervous about symptoms you started feeling about a week after having unprotected sex.
First, there are many things that could cause the symptoms you describe. In terms of HIV transmission, there is a risk based on unprotected sex if your partner is living with HIV and has a detectable viral load (with regular treatment people living with HIV can get to a point where they cannot transmit it to others sexually - https://h-i-v.net/living/undetectable-untransmittable .
There are many testing options if you believe you are at risk of contracting HIV. It may be helpful to know that window periods of when you can test can vary (your doctor can help determine this) - more info on those window periods here: https://h-i-v.net/test-types. With that being said, it’s still important to get tested regularly and speak about any symptoms you have with a doctor you trust. I hope this is helpful. - Liz (Team Member)