I didn't get my mom anything for Mother's Day?

Whenever my brother and I asked her, she says "I don't want anything except a clean house," so that's exactly what I did today with my brother and dad. Later my mom and I went to lunch and she kept saying how this was the best Mother's Day ever because she got to spend it with her best friend (me) and the house is clean. Now, she's all bitter saying we don't appreciate her and she likes the small things like a gift and cards. I'm so confused? I feel like the WORST daughter ever because of this. Suddenly, she's humiliated when all my brother and I did was do as she wished and wanted. I could cry right now because my mom is my best friend and she never expressed to me how much this day meant to her. Maybe I'm stupid for not at least getting her a card, but when she says she doesn't want anything, I'm not going to get her anything. I did make her brownies though, and that's something she wanted. Anyone else like this?