What damage remains? METH/four years after?

I am 20 now, and I used meth from age 14-16 heavily every day, every night consistently. I quit cold turkey with no wind down from this pattern. I am curious about the damage done to my nervous system. I have always had a healthy diet, active and musical life style. I have Rheumatoid arthritis and smoke cigarettes, I also drank beer and smoked pot during the meth abuse period. What kind of shape would my veins be in as an ex-meth using waning smoker? And is the past drug abuse the reason I am always overly aware of my surroudings (if someone turned in their bed in the same room It would sound like a drum roll to me, why)?
A summarry of what my question was that I did meth for 2 years BEEN CLEAN for 4 years having quit cold turkey, with NO relapse, and I CUT DOWN on cigarettes severley and WAS ALWAYS HEALTHY. What damage would remain to my nervous system, I’m still hyper aware of my surroundings.
Meaning I dont need to lose wieght… =)

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