Thank you for using JustAnswer.
Erectile Dysfunction or ED i not uncommon complaint.in young males like in your age, it is rare to have some orgaic cause for erectile dysfunction..
Only if there is uncontrolled diabetes over prolonged time or some neurological disease or certain autonomic system problems like shy dragger syndrome etc..
With viagra or cialis or levitra, you can try serteraline 25-50 mg and in most cases this combination works well.
Talk to yur local doctor if there is any chance you can use prostaglandin injection or suppositories.
Also you can try yohimbine and ginsing extracts as it is claimed that it is of goood help. I beleive it is avaialbel on pharmacies by the name of vigorplex.
If there is any emotional or psychological pressure or issue, that must be taken care also as it is one the major reasons in young males for ED.