In your example, “hid” is the past subjunctive of “to hide”. This is similar to the 2nd conditional, which we use to talk about an unreal present. The meaning is that the speaker is not hiding now, but should be hiding now (thus the unreal present). Some more common ways of expressing the thought in your sentence would be “I’d better hide now”, “It’s time for me to hide now”, etc.

Phil gave an excellent answer.

I know Hid is the past tense of Hide. But i don't understand why it's writen here.