I've had that, too, and it always happened when traveling alone. Suddenly I just wanted to be "teleported" back home for awhile to the streets I knew, the shops where I could speak English, etc. It usually passed in a day and I hope yours does, too.
Keep in mind that it usually takes a day to recoiver from jet lag for each time zone you've crossed so your body isn't back to normal yet. I agree with the advice to find a place where people speak English- a hostel or whatever- and you might be able to find someone who's been there for awhile and who has a better sense of direction than you. (Boy, I can relate to that- from what I've read, Japan is bad for the directionally-challenged.) Also- are the subway stops close enough that you can use the subway system to find your way back? If you find a subway station when you get lost, at least there's a definite route back to your hotel.
Good luck and let us know how you're doing. You'll come out of this feeling stronger.