My Son (21)has A Ration His Front Thigh For 3

my son (21)has a ration his front thigh for 3 days. It has "quite a bit of stinging pain" sent me a picture.It has red dots ,he also thinks he rubbed and picked at it a little.He is at college for the summer term and does not have a local doc, not sure if clinic is open in summer at college. But stinging pain seems odd, should I be concerned