What Is The Red Bumps With White Heads Around The Stomach And Waist Band Area?

Hi there, My son woke up yesterday morning, with a few red itchy looking spots (smallish in size) on his stomach - waistband area. He had wet his bed, so initially I though the redness was because of this (his sleeps on his stomach). However, after a shower, they looked more like spots, rather than a red area...we suspected insect bites? He has one on his upper thigh too. Today they are looking angrier...some have white heads on them. Also he has one spot with white head on his eyebrow and one under bottom lip. Also, he fell over in the garden and grazed his elbow a couple of days ago..we have have had a bandaid on it...but now there are also small red bumps with white heads around this area too. Any ideas? Should I take him to see our gp? Thanks