DAE Feels very weird when they get high now

Why do I get terrible anxiety from weed now when I used to smoke heavily

I started smoking when I was like 13-14 and by 15-16 I was smoking a lot sometimes up to 4 backwoods a day. Then I stopped smoking consistently for about a year or two.

Now whenever I get high it feels completely different. My heart feels weird my chest feels weird random parts of my body feel weird and I start getting anxious like something bad is about to happen. If I get too high I end up convincing myself something is wrong and it turns into a terrible experience.

What confuses me is I used to smoke all the time with no problems. Now I can’t even hit a weed pen more than once or twice or smoke a whole wood by myself without psyching myself out.

Has this happened to anyone else after taking a long break from smoking and if so why does weed suddenly affect me so differently now when I used to have such a high tolerance?