Completely off topic, but maybe useful anyway:
Tokyo (and a lot of other places in Japan) can be booked up quite a bit in advance (more than almost any other place).
If you are stuck (or for the vacation part), both dorms and capsule hotels are OK (japanese people are very polite and not making much noise etc (so most turists behave very well, too).
There are two different metro companies (maybe more), that runs a bit ‘parallel’ (but you can buy a more expensive ticket that can be used on both if you can not figure out 'where the different run) and out of ‘centre’ the information is in Japanese, so Maps.me or something similar is very useful.
The metro stops ‘rather early’, so if you go drinking you might have to stay up until morning or take an expensive taxi