what's so funny?!

So, lately, I've just been laughing all the time. It's a good thing, and reminds me of being younger, but I can't explain it. I've always been one to over-laugh at a joke, or mentally re-visit the joke and start laughing for no reason, but for the most part, especially since I began working, I've had much more composure. Not lately. I'll be in the middle of a meeting, and I'm seriously bursting blood vessels in my head to try and keep my laughing inside. What's so funny? I have no idea. It could be anything, and it just sets me off into a mental and sometimes outward laughing fit. A few days ago I just had to walk away from a co-worker's cubicle because I was laughing and really couldn't explain why.
I mean, I know why sometimes, but it's the length of time that I think it's funny that has been extended, as well as the frequency of me getting these flashbacks to something funny during inappropriate times....like during quiet time (I call that the after lunch time when everyone is full and tired), or like I said during meetings, or even during a one on one conversation. I notice it more at work, because in social situations or at home I can just laugh and it's not really thought of as strange compared to during a conversation at work about work. Anyway, I don't really mind it. It's fun, and I enjoy it, I just hope people can give me a break. I've always looked for funny stuff. Growing up SNL was something I couldn't wait for each Saturday, and that type of humor really gets me going to the point I can't breathe...poor Matt can agree...tonight an SNL special was on and I was laughing way too loudly...like maybe to the point of sounding like an animal. Then, Wally comes running and jumps in my lap probably thinking I'm dying. Anyway, here's to laugher for no good reason. There's really nothing wrong with that.