i take a clean safety pin and poke my in grown hairs to release the pus it don't hurt as bad as u would think. then i dig the hair out but i usually get them on my legs never had one on my chest

I have gotten that a lot from wrestling and judo. At least from what I can see of it. It is an ingrown hair that has become infected. That is why the redness spreads and also why it doesn't come to a head like a pimple. If you have or can get some anti-biotic it will neutralize it. Eventually a head will appear because the point of the ingrown works its way to the surface again.

Use clippers instead of a straight razor & this would never happen. But if you need that straight razor then Nivea after shave always helps. Hit it with Isoperal alcohol & hot compress. Before it turns into a boil & ends up scaring

take a trip to the ER if it gets bad.. tell them you played football or something
and you took a hit to the chest. Even better is one of the local places where
you just pay them and walk out.

shit dude i get ingrown hairs all the time. i try and exfoliate over areas which i shave and areas which are prone to acne. warm compresses help too, as levelup mentioned. i had a stye once and using warm compresses really helped that. acne really fucking sucks.

It seems like an ingrown hair. If so, it takes a while to clear - several weeks. To eliminate the possibility of gyno or other estro-related issue, check your nipple for soreness. Feel directly over the nipple pushing firmly in narrow circular motions. If you feel nothing directly below the nipple, no lumps or soreness, then it's highly likely an ingrown hair, or possibly sensitivity to shaving cream, or you may have simply irritated the area via how you shaved it.

Use a hot compress man...looks like an ingrown/infected

Honestly if that happened to me I would think it was a hair or acne. The hair could be growing underneath which would make a red bump. You don't look puffy to me. Wait and see what the other brothers say. Good luck bro