I never had in my life. i m 20yrs old and when my mates say they had with many girls it frustrates me?

i never had in my life. i m 20yrs old and when my mates say they had with many girls it frustrates me. i start thinking i m useless. i never had in my 20 yrs life, it ruins my whole life- work life and social life. i couldnt speak to customers nice and couldnt wear a smile on my face. i dont even feel like talking to people at times because i undermine myself saying i m not a man. it just frustrates me and kills me every moment. dont know what tot do. tried having girl friend. but split in few weeks. it also affects my personality. i always think i m not smart as other men coz i nevr had . i m going mental thinking of it and too shamed to try prostitutes. help me out.