On my way home last night (about 10:30, had been doing my hobby not out drinking or anything) I started feeling incredibly nauseous. When I got home I felt horrible and instinctively went and sat on the bathroom floor for a bit. At about 11:00 I vomited copiously. Afterwards I felt a bit wobbly but otherwise mostly alright so I just went to bed to sleep it off. This morning I feel pretty much ok, just a little washed out, although I haven't really tried eating or drinking yet. I was only sick the once and I'm not sure why. I'm feeling a bit guilty as I probably feel alright to be in work but I don't want to potentially infect people! AIBU to have called in sick?