What Are The Chances Of Fertility Having One Testicle Due To Inguinal Hernia?

Good day Sir/ Madam
My name is hisham, im a pakistani born and living in Dubai, date of birth 29-9-1984
i am worried about my fertility as everyone keeps telling me that i wont be able to have children ever.

when i was 40 days old i had a problem with my testicles, as this is what my parents told me, Doctors over here in dubai were not willing to operate as i was not suitable for it because of that age, but they did perform a minor surgery to relieve the pain, for approximately 21 years there were no symptoms of hernia or such disease but at the age of 21 i started having trouble with my testicles every morning when i used to wake up it would feel as is if the left testicle have moved upwards and left its place and i used to stay in bed all curled up and suffering with an extreme amount of pain and the duration could go from 10 minutes to sometimes 1 hour.So i went to our family doctor and told him about this whole situation, he referred me to a doctor in a government hospital where i was diagnosed with a left inguinal hernia and soon i was operated for it, now i have only one testicle remaining which is the right side. I have never had sex and am not married till now, i have tried masturbating and normaly i do it once in a month or so. but once i tried masturbating twice in a row and was successful. after that i never tried it again.
now the thing is all my cousins and my friends keep telling me that i wont be able to have children and things like these, but when i was operated my doctor who is also my relative told me that it will work properly and that i will be able to have children but i doubt him and his answere because he could not face me when he was giving me this answere. and many older people told me that im not fertile enough.