I cant login on windows xp pro???!!!?

I have a compaq evo n1015v and i accidentally deleted the user account!! That was the only account to! Anyway i can either recover it or restore factory settings? I've tried typing admin and administrator and that didnt work either. Then i tried the f10 f8 f2 and f11 on booting! What can i do? And i lost the windows xp install cd