No, it doesn't sound like you have HIV or lymphoma. It does sound like you have anxiety, though. So I guess you're in the right place.
Listen, right now you're caught up in a cycle of fear-symptom-fear. Because you're stressed, your body is reactive, and every time you feel one of these physical manifestations, you react fearfully, thereby ramping up the stress in your body, which only makes it MORE reactive and symptomatic. To treat your anxiety, you've got to short out that circuit, so to speak.
When you react fearfully, what do you do? You jump online and research your symptom, or you run to the doctor to get more tests, or you run to your family and friends to receive confirmation that you're fine and not dying. As good and comforting as all of these things feel in the moment, they're actually what mental health professionals call "negative reinforcement behaviors" because they help reinforce, in your mind, that you NEED them to deal with the fear, and also they reinforce that what you're experiencing bodily really IS dangerous, because despite tests and reassurances, your body keeps being reactive and symptomatic.
So, you ask how to deal with your anxiety—there's lots of ways. First, try and curb these negative reinforcement behaviors. When you get the urge to panic or jump online or run to the doctor, take a moment and see what it is you're doing. It doesn't really matter what else you do as far as treatment is concerned, if you don't get a handle on these types of behaviors, you're not going to feel better. Acceptance that what you're experiencing is anxiety and nothing more is the other CRUCIAL element to recovery. You have to quash that little voice in the back of your head that says, "but what if it's something else?"
Anxiety treatments that people on the AZ have found helpful are things like talk therapy, cognitive behavioral therapy, medication (both anti-anxiety and antidepressant), meditation and breathing exercises, yoga, exercise, hobbies and changing eating habits (there are more). Have you talked to a doctor about anxiety and how to possibly go about treating it? Treatment is not a magic bullet—it won't make you feel better right away, but if you're diligent with it, you WILL feel better, I promise.