"to my room"

Bonjour Helen,
This seems like a very good question to me; I had not looked at it like this previously. I will be interested to learn the reasoning, too.
Bonne journée

I'm hoping Aurélie responds:)

Hi Helen,

the use of directional prepositions in French is different from English. Also, the French don't differentiate as acutely between being somewhere (location) and going somewhere (direction).

Je suis dans ma chambre = I am in my room.
Je vais dans ma chambre = I am going to my room.

The difference of location versus direction is carried by the verb (je suis vs. je vais).

-- Chris (not a native speaker).

Bonjour Chris,
Merci for your excellent explanation.
Ron