1. Symptoms are not a reliable way to diagnose HIV. Reason being symptoms are flu like...and so are the symptoms of thousands of infections! Don't base diagnosis on symptoms. Only testing at 1 month and then again at 3 months will be conclusive.
2. Lumps on the back of the knee are NOT signs of HIV infection. Lymph Nodes are located in the neck, under the arms and at the groin. And only a doctor can tell you for sure if they are swollen.
You do not have HIV.
If you are worried about the lump, go and see a doctor.
There's a cyst that can appear on the back of the knee, but I can't remember what its called. Its harmless.
Baker's cyst? A colleague of mine had it. I remember him saying that it was quite painful though, especially when he walked. But he was an older gentlemen and his cyst was linked to arthritis, so that made it more uncomfortable I seem to remember.
Anyway, don't know if thats what you were thinking of.
swollen lymph nodes either singly or several are absolutely NOT an HIV specific occurence. They can happen for all sorts of reasons that have nothing to do with HIV.
So no matter what your mind is busily telling you otherwise, they aren't YET ANOTHER OMINOUS SIGN that your worst fears will come true.
You need to give some credence to your negative test results. The average time to seroconversion is 22 days. All but the very smallest number of those who are going to seroconvert will do so within 4-6 weeks after an exposure to the virus.
Don't prod your nodes. Don't feel them, examine them or anything. Leave the blighters alone. Poking and prodding the dratted things makes them swell
RELAX Be COOOL