Yes, a street that is narrow is referring to the width. It is not wide. A street that is cramped has other people on it, making it difficult to move. In either case, that road is more difficult than one that is wide and spacious.

They are similar. To me cramped would be more uncomfortable. It gives the idea that you are pressed against, its tight.

Narrow is something you you see not wide and cramped is something you feel not spacious. That's it. You can see a narrow street and be in a cramped (crowded) bus.