Health good no scalp infection, illness.did excessive ejaculation of sperm fr 2 yrs increase testosterone level very high cause baldness at age20?

No: So testosterone (t) is converted into dihydrotestosterone (dht) which is can cause hair loss. Therefore, higher t might lead to higher dht. But those w/normal t can have relatively higher dht, too. Don't forget that genetics has a big factor in hair loss (think male pattern baldness) so look at your dad, his brothers (your uncles), your dad's dad, etc, & your brothers. Medications can lower dht.