I Don't Sweat Anymore I Get an Itchy Stinging Type of Feeling Wheni Get Hot Why ?

ok i stopped sweating in january and when i get hot or almost sweat i break out in little bumps and my skin starts to itch and sting like if your leg falls asleep and i went to the doctor and they told me to get my thyroids check so i did and my tsh t3 and t4 came back normal now i had a rotten tooth a while back but got it pulled after it hurted to bad and i got a tattoo on my sternum a day after christmas and i was hospitalized in january because of my heart was racing