How long is a piece of string? No one can tell you how long it will take for your skin to heal. You MUST leave well alone and allow your body to heal the cuts and not aggravate it any more. I trust that you have not been using any implements to get the cuts!
It may be that the irritation and cuts are from a dry skin, which may be aggravated by using normal soaps. The other condition that can cause a redness of the skin with irritation is a fungal infection called Thrush. When you touch yourself, always ensure that your hands have been washed, and always wash your hands after you have used the toilet.
I suggest you wash yourself using only water, a soap that has the same pH level as our skin and baby washes may be fine. Do NOT use any normal soap, shower or bath gels, these will dry the skin and will irritate the already sore skin even more.
You can have a soak in salty water, or Epsom Salts. When bathing you can put in 2-3 cupfuls of Epsom Salts into the bath water.
If you do have a fungal infection, this would need to be treated by a specific anti-fungal cream that you can buy from the pharmacy or the doctor would prescribe if he felt this was appropriate.
You could purchase a emollient from the pharmacy that you can use instead of soap and this will help to moisturise the skin. If you have a fungal infection this will not heal it.
As a home help remedy, after washing and gently drying your problem area, you can apply natural set yogurt. This will cool down any inflammation and also help with healing. You would need to put on quite a bit and it will feel cold. You can apply this as often as required.
Wear clean underpants every day.
Do be aware that bacteria can enter through cuts in the skin and infections can spread. If the skin shows no sign of healing over the next few days, make an appointment to see your doctor.
Do NOT masturbate until you are well healed.
Put aside your embarrassment, you will not be the first person the doctor will have seen with a sore penis.
Penis problems can happen even if you did not masturbate; fungus infections can also happen on any part of the body and also in the mouth; so do speak with one of your parents to get you booked in to see your doctor so that the doctor can prescribe the appropriate medication if needed.
Preferably you should get checked out by your doctor.
Okay, thanks. Think I'm going to not masturbate for awhile as well as not use soap on penis & see what happens.
And if that doesn't work than I'll have to just go to a doctor about it.