I am a 25 year old male and i am able to get erection but maintaining it for long is difficult for example while wearing condom i loose erection or while masturbating if i stop stimulating it i loose erection very quickly i need to keep stroking it. I consulted a doctor who suggested me tadlafil 5 mg and when i take tadlafil 5 mg everything works fine but i am scared that i have to keep taking it every time before sex and all my medical reports are fine . Idk what to do ( my urologist also suggested to keep taking tadlafil 5 mg continuously for 2 weeks even though i don't have sex) is taking tadlafil continously is advisable? Kindly help i am really worried