Struggling with Homesickness and Overwhelm

This will be a bit long for some explanation. I could use some help with homesickness. I also need a bit of a vent because I'm feeling down but I need to stop bothering everyone irl about it. 😅 I came to visit my mum & bro (they live in a town over an hour from my home) and was meant to stay here from Wednesday Aug 3 to Sunday Aug 7. On Sunday when I'm meant to leave, my grandfather (with whom I live with at home) has contracted COVID and so I cannot return home yet. My mum's house is really uncomfortable for me. It has a lot of overwhelming aspects sensory-wise (specifically due to uncleanliness), the bed is broken, I don't have my typical comfort space that I rely on at home, I can't follow my daily routine, I miss my cat, etc. I rarely leave my comfort space for any reason other than appointments when I'm home, because I rely on the controlled environment I created for myself there. What can I do to combat this? I'm starting to feel physically unwell because of the stress. I wasn't expecting to be unable to return to my safe place on schedule and now I'm progressively becoming more overwhelmed. I feel really silly for it. /: