Ethosuximide medicine

my neurologist js put me on this also with zonisamide and it’s been 3 days and i’m super shaky, i’ve had sleeping issues, increased heart rate which makes me scared i’m gonna have a seizure every time idk why, and when ppl speak i can’t focus. what they are saying is literally going in one ear and out the other. my brain fog has increased. i feel so dumb when ppl talk to me.