Hi, and thanks for your question
Yes, the window period (the time between when a person comes in contact with a sexually transmitted infection and when the STI will show up on a test) for HIV using the 4th Generation HIV Antibody test is 3 months (90 days). This means that if you have a negative, or non-reactive, test more than 90 days after the exposure you do not have HIV.
The reason that HIV antibodies have not been detected in your case is presumably because you do not have HIV.
The symptoms you are describing are not specific to HIV and could be attributed to any number of different causes. If you are concerned about the symptom, you could revisit your family doctor to discuss the symptoms themselves, knowing that your HIV test is negative.
Let us know if this does not answer your question or if you have any more questions or concerns.