Hi yesterday I was travelling by bus and suddenly started t shiver felt suffocated. Is it anxiety?

Just hoping to see if anyone else has had the same experience as me and any success in treatment.

I am a 24yo female that in the past year has been gaining weight. I have not changed my diet and eat very healthy, dairy-free and fruits and vegetables. I should probably eat more protein but I get healthy fats through nuts, avocados, etc. I am also an avid exerciser, going to the gym 4-5 days/wk

I have been diagnosed with PCOS by a gynecologist as I have not had regular menstrual periods (once every 6 months or so).

I've noticed more symptoms of hypothyroidism lately-- tingling hands and feet, anxiety and depression, muscle strains and joint pain. My holistic doctor did blood work and found a slightly low T3 level.

I guess I'm just wondering if anyone has advice on how to tackle these issues?