Viagra... before workout

Hi all,

I bought suhagra 100mg from medical shop... I took the pill and was watching porn... I waited for almost two hours... But Viagra didn't do anything... It was normal erection for me... What can be the issue?

Importantly, I was testing Viagra effect because I want to take it before my workout... Is it possible?? Does it help anyhow in pumping up lifts in gym??

Please help and share experiences...

Thanks