I am a second year student who just moved into off campus accommodation with 3 friends. They are studying Computer Science whereas I am studying Computer science with AI and now I have a very different timetable to them. We only live 5 mins away from campus so they keep inviting anywhere between 3 and 5 of their friends around without telling me. They are incredibly loud and I often walk in not expecting them to be there. We don't have locks on our doors and one of them came into my room once without knocking. I don't feel like I can do normal things such as showering, making food etc when they are around I fell like they will be staring at me.
They usually only come around twice a week but they are incredibly irritating when they do and there is never any pre-warning.
Should I tell my flatmates I don't like them being around or should I try and stay out of the flat when they're likely to come round?