*Waiting for doctors office to call back*

Yesterday my 16 month old had has second flu shot and a hepB vaccine. Later in the day he developed a light pink, slightly raised rash over his trunk and very slightly on his arms and legs. It didn't seem to bother him and no other symptoms. He also had a bit of pink in his cheeks, like he looked feverish. But no fever. This morning it was the same but over the last two hours one cheek has become very vividly bright pink. It looks almost like his cheek is sunburnt. This doesn't seem to be a common side effect of either vaccine so I'm not sure if it's an allergic reaction or just coincidental to the vaccines. Any thoughts on a rash of this type?