my baby has a bloodshot eye😞

Kayley • 24 years old, I have a little boy who’s 4 and I’m TTC my second baby!! 👶🏻
My 8 month old has been run down the last few days, slightly hot, not eating his solids (still drinking milk), no energy and quite whingy. We assume that he is cutting his first tooth, but since yesterday morning he's had a bloodshot eye, only the one side of the eye is bloodshot. Any ideas? Doctors is closed for the weekend so wanna know opinions.