tired...running

i just came home from a 20 miler not too long ago. i haven't run 20 miles since before jay (and at jay i did 33 miles)--so it's been a month and a half since i've done any runs longer than 16 miles. i'm not sure what it was today, but i had SUCH a tough run today. mentally, i was so not ready, though i was excited. however, i got dizzy, had stomach issues. running around downtown nyc, past the artists and the stockbrokers and the hippies and the tourists and the lovers and the kids playing catch and the grandmas smoking tiny cigarettes and people eating delicious avocado sandwiches...i tried so hard to appreciate everything, but it was so hard. i ended up making lists in my head of good things about nyc, and practicing tonglen so i wouldn't suffer in my misery. but oh, how hard. i need to get back into it. i have a marathon in a month and a half, and an ultra, oh, sometime in nov or dec.