I have pain in my jaw, ear, neck and throat. It feels like a tightness. I feel no lumps, just pain and tightness. I use a night guard for tmj. What else can I do?

Find neuromuscular. I advise you to find a neuromuscular dentist in your area and heve them help you with these issues.
Evaluate Nightguard . Your symptoms could be related to many different conditions. However, since you have a history of similar symptoms & already wear a nightguard, a logical place to start would be with an assessment of your nightguard by your dentist. Nightguards have to be adjusted or remade occasionally. If that doesn't fix it, then your dentist will either diagnose something else or refer you properly. Get help.
Night Guard TMJ. Night guards are not design for TMJ problems. On the contrary, it will cause more pain and discomfort. Go to see a neuromuscular dentist.
TMJ. It looks like your TMJ is still bothering you despite the night guard. Do you clench your teeth during the day? Ask your dentist for other advice. See a dentist who is specialized in tmj.
TMJ Expert. Your nightguard was probably made by your dentist who knows little about TMJ. See a TMJ specialist. Any dentist can be a TMJ expert with the proper training and experience. Most commonly, oral surgeons, prosthodontists, and orofacial pain specialists. Ask your MD, your dentist and your dental society for referrals.