I've had a cut on my penis, it stopped bleeding after putting on a band-aid, area is red itchy, should i be concerned?

This could be a fungal infection-you would need to have it looked at to be sure but red, itchy and an open area is often related to a fungal infection. There are over the counter anti fungal creams you can try to see if that allows it to heal. If not, then definitely see a doctor. Good luck!

Keep the area clean and covered till it heals. From your description should heal if only skin deep