is this something in my relationship that should worry me?

me and my gf (18M, 18F) have been together for three months but have been friends for three years. so little problems like this concern me.

my gf has an anxiety issue, and she’s understanding to the point where she gets extremely worried and it ruins her day when I speak to her about the fact that im not doing well. (and we both haven’t been doing well recently, for our own separate reasons, nothing to do w each other)

it always ends up as my fault for upsetting her and it doesn’t help me when I’m going through difficulties. I’m always extremely understanding of her problems and constantly put aside my responsibilities to care after her and make sure she’s feeling fine. I have no problem keeping my issues to myself, I just got kinda sad at the thought that I can’t talk to her about these things when I do the most to listen to her and cheer her up when she’s having a bad day. I understand her issues with anxiety and stress and it’s not something she can help either though.

what do i do in this situation? is it a red flag? do I talk to her about it? I don’t wanna make her guilty over something she can’t control.

tldr; my gf can’t listen to my feelings and my problems while I do the most for her, and its okay but it feels unfair, even if it’s never her intention.