You could be facing a problem of Erectile dysfunction. However, a detailed history and information about associated risk factors and history about the complaint is needed to confirm the diagnosis. Only can then a definitive management plan be advised. Masturbation habit, pornography use, concept regarding sex, etc must be studied. Most importantly, with suitable instructions and if required, medications it can be completely cured.
Next Steps
For more information regarding this problem and advice on management you can consult directly here on practo.
Health Tips
Don't worry. It can be cured.