Rashes or what?

Hye mommies, anak baru 6 bulan 12 hari, baru 3 hari lepas vaksin 6 bulan, already started semi solid food, a good eater, perasan naik merah2 ni start dari belakang leher, muka then badan. Is that allergies atau ape ye? Ada mommies face the same problem? Mind sharing, tq