I am so sorry but I am not feeling well. My stomach hurts a lot and I'd better stay home.
I really wanted to go, but there is a huge storm and I cannot get out from home. It's too dangerous.
I have a massive pimple and I am afraid it is some kind of allergy. I think I am going to the hospital.
It is a shame I cannot join you, but I have just undergone surgery and my doctor said I should rest at home.
