bro your still 21, your test levels are still raging.. make do with this untill you are about 25, you can still make some good gains..... what does your diet look like?
you wanna do something without being extreme but aas are pretty extreme? you say you just wanna put on a few pounds you can easily do this naturally
if your gonna go aas route there no halfway, your either in it all way (gainin 15 or more pounds and being a monster)or nothing at all
you can get acne, you can get hairloss, etc etc...... theres really no 100% safe side....... so you gotta consider this, also if your still feeling great everyday and ragin sex addict and lookin goood i would keep up being natural till around 24-25 when your nat test levels start to really drop
also stay away from the over the counter orals sold on websites and gnc etc like superdrol, they are very tempting to the crowds who wanna start out b/c of people makin huge gains on them but the side effects are greater then the gains