Should i be concerned about jaw/hand tremors? it's as if i were shivering cold, but very slight; not really visible but i feel it all the time.

Yes: I would recommend an evaluation by a neurologist. There are some medications that can cause this as a side effect or there could be a neurological condition that is developing.

Essential tremors?: You may have benign essential tremors or benign familial tremors if there's a family history. Though you're a bit young I've seen them in teenagers so it's possible. The hallmark of ET is it worsens or becomes more noticeable with activity of the hands or head and goes back to baseline at rest. Alcohol can extinguish them in a large % of cases but they come right back. Talk to your doctor.