was I [20F] selfish on the phone with my mum [54F]?

I’ve been going through a lot as of late, just ended a relationship with a guy who was 44 after a night where he grabbed me hard and called me names then threw his chair against the wall.

We called today because I was having a rough moment and I told her all about what happened and we discussed it and she helped me a lot and then she was getting in the car with my dad to go to the chemist and I needed to pee so I presumed the call would be ending there roughly (because I didn’t feel right asking to hold the call while I peed because she was getting in the car anyway so I presumed it was ending,) and was rounding up the phone call and she just sounded upset and I got the feeling she felt I was being selfish. It’s her birthday tomorrow and I said I’d come over and she was even saying she’ll make me a vegan dinner (because I’m vegan whilst they’ll be having steak,) and I could tell there was resentment in her voice like she felt it’s her birthday and she shouldn’t have to be doing that. Which is fair if you think about it. I think she felt like I just called to verbally dump and then was like “okay I’m happy now bye.” I said are you okay, and I hope you don’t feel like I was just dumping etc, and I brought up her birthday and her upcoming surgery in a few days (on her leg to remove a tumour she’s had for years,) I just don’t know what to say. I do care I just feel like I don’t seem to do “it” well enough for her or my dad by their estimations. And she denied she felt anything like that but she just sounded resentful or upset and I’m worried I was being selfish.

Was I being selfish?

Edit: selfish as in not caring enough about her or asking about her life and only caring about mine

TL;DR: called my mum to talk about stressful stuff, started rounding off the phone call when she was getting in my dad’s car and because I needed to pee, could tell she felt resentful or like I’d been selfish, her birthday is tomorrow and she has a surgery coming up for a tumour removal on her leg, I’m seeing her tomorrow, was I being selfish?