Is that normal to feel so..?

Fine night- I was so happy last night when I'm having dinner but today I don't feel the same after my dinner. Got to know that I'll have a new roomie next semester. Though I've seen this coming but I didn't realized that I would be this sad/down. I have thousand of reasons to console myself but the truth is often more cruel than we could think of. Seriously got so distracted and lost concentration with my assignments.