Hi Joe, now you have learnt the hard way when people say dont do drugs now you have found out why, and just why do synthetic, its just some made up s**t that some one has put together to act like to real thing, as just does not care about its side effects.
So what can you do? I think the best thing you can is wait give it a couple of weeks lay of masterbating (playing with yourself, spanking the monkey) try and just put it to the back of you mind, the body is a great healer if you let it, and try not to false it.
And if you think your depessed now, if you cant get it up again then you will really be depressed for life, but just relax go out and enjoy yourself but dont date any hot chicks.