We had sex last night and I feel weird , should I just use car and no more sex or connection until I leave?

So me and my ex decided to break up but I am currently living with him while I save for another car and also so I can go to nursing school but it will only be for the first week of June. I found out he recently been talking to another girl for three days now. He told her how we broke up and I’m living with him for a while also using his car.
We had sex last night and I feel weird , should I just use car and no more sex or connection until I leave?
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