['Have you ever been in a situation where you had food on your face and you walked around for awhile without anyone telling you? This just happened to me yesterday and I was so embarrassed!', "Of  course I have, it's really hard", 'Yeah, I was mortified when the person told me about it - especially when we were talking for about 5 minutes.']
Was it in the morning? Did you rush home immediately? How did you manage?
Just the other day, I was quite embarrassed at work. I was wrapping up my lunch and talking to a coworker. I must've been talking to her for about 5 minutes before she said I had food on my chin.