Could it be eczema maybe? My boy had red spots all over his body that he was scratching but it was the worst at his neck, stomach and face, he is almost 4 months now and at his 3 months appointment the doctor said it's eczema and gave a special medical cream that worked very nicely, and also gave a special soap and bodymilk, since then his head and face is still not ok coz it just keeps coming back, but his stomach is perfectly fine now