Anxiety Support Group
Anxiety is a physical condition marked by intense and persistent feelings of distress, fear, angst or dread. General anxiety caused by routine day-to-day stresses usually passes quickly and is experienced by almost everyone at one time or another. However, such feelings that linger over time and are very difficult to cope with, and which lack a clear cause, may indicate...

Make sure you stay hydrated, relax those tensed muscles and breathe.
Best wishes.
Welp - except for the squinty eyes - that sounds like hyperventilating - which is a pretty common symptom of a panic attack. You get too much oxygen in your system when you hyperventilate which can make you feel dizzy, light headed and "high" - so to speak.
The issue is that when you are anxious and heading toward a panic attack you physically get tense. When you tense up your body your breathing can go rapid and shallow - and that would be the hyperventilating.
You can help it by doing some of those exercises where you REALLY tense every part of your body as hard as you can - hold it - and then relax. You start at one end of your bod - your head and neck - really contract every muscle you can in your face and neck and then relax. Then you do your chest region, your arms etc. The extreme contacting and then relaxing helps to break up being stuck in a static state of tension.
That, or just talking works for me. If it is hyperventilating I can recognize it right away as soon as I open my mouth and start talking to someone. I'll... be like... doing a... short inhale... every... couple words... and - yeah then I know I' m hyperventilation. If I just keep talking along it really helps to get my breathe rate back to normal.