Age is 23. Had testicle pain. Dr. Suggested veltam 0.2 in morning and veltam 0.4 in night. Semen volume got reduced. Had taking medicine for 1 month. Pain had gone but from 8-10 days my sexual libido has reduced and there is difficulty in maintain erection. Had stop taking veltam from 6-7 days. Semen volume is normal but reduced libido and unable to keep erection is worrying me as it has never happened before. Please help.