Heart pounding, due to stress? Anxiety?

I am a 27 year old women, unmarried. Normally I am healthy but I have hypothyroidism since teenage. Since last 2 months I am experiencing high heart beat sometimes, I get palpilations. Sometimes I can see and feel my heart beating in my chest, stomach and neck regions. Generally even while resting is around 70 beats per minute, sometimes 80. This didnt use to happen before but recently started since 2 months. It is due to stress and anxiety? Because I have been under a lot of stress and anxiety since last 2 months due to some reason and when I think about that topic my heart beat rate generally increases. It is only due to high stress and anxiety? Or it can be due to any other reason. Please help I am really scared.