Jaw pain after first acupuncture session

The best person to ask is your acupuncturist as they would be familiar with all the symptoms you came in with, your overall history and what points/techniques they utilized.  Generally speaking, however, acupuncture is largely stimulating your body's own healing/immune mechanisms and doesn't have an ability to "force" anything to happen.  What can happen in cases of treating eye/ear/sinus/facial pain type issues is that things, particularly in the sinus cavities start to move - which can cause temporary pain and/or even correspond with the beginning of a sinus infection or related issues that would likely have started anyhow.  

In your case, again can only guess with the info provided, it seems likely that there was a possible reduction in inflammation around the upper jaw/ear areas that may in the short-term cause the body to re-balance the tension it has been holding in those areas - this could lead to both movement in the sinus cavities, possibly contributing to swollen lymph nodes, and/or clicking from the structural changes of loosening tension and/or inflammation in the area.  Again, you should ask your practitioner their view as they would know best, but in general "side-effects" of acupuncture areshort-lived and in most cases, if they happen at all, work themselves out over the first 3-5 treatments.

In the most general terms possible, as a practitioner we would like to see either a moderate improvement or at least an irritation of symptoms from the first few treatments - with the poorest prognosis coming from noticing no change good or bad.  In general terms, again, as this certainly doesn't apply across the board - any change from the first 1-3 treatments good or bad usually indicates a more positive longer-term prognosis.