Emotionless sex is a difficult thing. Many people will develop feelings for their sexual partner after rubbing nasties for a while. While not universal, it's a fairly natural thing.
We've been told that we should be perfectly capable of having a stream of one night stands without any further consequences, but this is not right. Not everybody can engage in emotionless sex. Further, some people need some kind of previous connection. IE: I'd have trouble bedding someone I just met. I need to know her to a certain degree. While physical attraction goes a long way, I have to feel confident in both of us being able to have a good time.
Rebound sex can also be very troublesome right after a breakup. Guys find themselves uncapable to perform, girls fail to lubricate or experience vaginismus (oh boy,
the drama)... It's a mess.
I've never experienced a bad breakup (or a breakup at all, I've been fortunate enough to always split in good terms and from mutual accord) but I'd rather console myself with lasagna for a while and then go on trolling for some.
But yes this is more holdover of it being a new relationship, so we just haven't discussed it yet.
It goes without saying, but get tested. I've only practiced barrierless sex with my current girlfriend, and that's because we knew we were both freshly tested and mutually exclusive. I'm fairly certain there are a number of places that will test you for free.