Appetite Changes

I've been a ravenous pig lately.  I'm always hungry and rarely satiated for over a couple hours.  I have of course run more weekly miles than ever before in my life and this is the first time I have noticed it affect my appetite.

After Saturday's 20 miler, I must have eaten 5 complete meals.  I was so hungry.  Now, it kinda makes sense that I was so hungry as I had burned close to 3000 calories on that run and needed to refuel, but wow, I could not be stopped.  I am making conscious efforts to refuel myself properly and not with garbage (although I do indulge in Swedish Fish more than anything else). 

Now, last night, I was not hungry at all.  at all.  not even a desire to eat.  I had a handful of pretzels with a glass of milk as I finished my book (Hunger Games, loved it!) and didn't want anything else.  This is rare for me and I rarely miss a meal, but I just wasn't in the mood.

On a normal day, I wake up hungry.  About 2-3 days a week I wake up starving and have to eat even before I take my shower.  This morning, however, I didn't want anything at all.  I had no hunger, no desire to eat even.  I packed some breakfast with my lunch expecting my hunger to come back, but it hasn't yet. 

It's now 1130am and I've only had 2 chocolate chip cookies - I know, great fuel.  And it's not like I craved them and had to have them; I work in a school and they were just there, so I ate a couple cause they were delicious.

Should I be worried?  I don't think so.  I'm not concerned with weight gain or loss right now, I just want to be properly fueled for my upcoming marathon.  I have a delicious sounding fresh salad waiting for me for lunch today and should be hungry by then...

I just don't think I should force-feed myself, but then again what do I know, I've never experienced this before and surely have never trained for a marathon.  Any advice?  Has this ever happened to you?