Relationship advice needed

M26 and F24 dating for over 3 months now.
Our relationship is going by very smooth and loving. Everything is so perfect about it. We even discuss future plans of being together and stuff.
But there is one thing that has been bothering me, and hence I am posting it here to understand whether I am overthinking or is it really something to be bothered about.
My gf’s parents and family knows about us but my girlfriend often tells me time and again that she does not want other people (other than family) to know about our relationship (until we get married)
For example: 1) She does not want me to be seen near her office as people will see us. A couple of times I have been there and she has acted so weird and uncomfortable.
2) She does not even want her childhood female besties to know about us with whom she shares everything
3) She would rather not respond to my calls/texts when she is around people so that they don’t ask her about who she was talking to

I do not understand if there is something to this behaviour or I am thinking too much. Other than this, our relationship is perfect.
Your views are highly appreciated. Thankyou!

TLDR: relationship advice needed