This movie could've been really good if the ending hadn't fallen so flat. It left a lot to be desired. (Spoilers ahead) In my opinion it would have been way more effective if they watched their friends die again or if they tried to stop their past selves from entering the house but couldn't.
It doesn’t seem to make very much sense that the time loop started in the bathroom but even if you were going to take that route making them be still in the escape room after "escaping" just felt cheap. It was kind of like the ending of the creepy pasta No End House.
Also, I might be missing something but that bit with the painting just seemed so off theme and the tea bit at the beginning which I believe to be a red herring to suggest that the group was drugged when they weren’t actually, felt a little bit forced and clunky. It wasn’t really necessary.
If the group really was drugged then they put way too much emphasis on the tea, it was super unnatural. All things considered it was suspenseful and leaves the viewer with a lot to think about but really took the grade school short story approach to the ending.