For 3 days, I have had a very painful scalp, sore throat started today. Some ear pain and some jaw pain. Tylenol (acetaminophen) works on the scalp pain. Any ideas?

Pain. Pain is your bodies way of texting you that there's something wrong. It may be infection. It may be muscle/joint dysfunction. It may be parafunctional habits. If problem getting worse, the severity of the problem is increasing. Call both your dentist and your physician for initial examinations. They may rx your problem(s) and/or refer you to specialists for further evaluation and testing.
cranialfascial pain. It is possible you are grinding and clenching your teeth resulting in ear and scalp pain. The muscles that support the jaw connect to a layer of tenden that covers the head like a swimmers cap. If you are unaware of doing this while awake you may be doing it in yoursleep. First thing when you wake up put your palms over your muscles anterior to your ears and open wide..If painful see dentist.
Could be infection. Check with a dentist experienced with TMJ or bite related problems. First need to rule out any oral infections or throat infection.