Rash On Privates

Hi... so yesterday I had a party where I got a little too drunk, and I let this boy finger me.. I woke up this morning and now I have a rash down there, I don't know what it's from... earlier on in the day I did shave my privates, I had read somewhere that deodorant helps stop razor burn or ingrown hairs from growing so I decided to try it.. so I don't know if the rash is from that and will go away in a couple days or if it's something serious... I would much appreciate people's opinions/input 🖤