For 2 months on and off I have been getting a smarting pain inside my penis, its worse when I shower and soap gets to it. Is there anything I can do to relief the pain

You need to visit a urologist to rule out any infection. For your urological health this is something that must be seen rather than diagnosed over the internet.

To J_9

Thanks for your answer, I have been to the GUM clinic and tested 3 times but all clear. I've seen my GP twice and he doesn't think there is a problem but thinks maybe an allergy. I'm very concered