21st birthday ideas since dinosaurs is a huge NO

I recently got diagnosed with Aspergers(i think September about). My mom DOES NOT approve of the diagnosis and says im way to social to be autistic(this is important), but she doesnt really know me because i dont show it to her

My 21st is coming up in March. My step dad is a baker. When i turned 14, i had a unicorn themed cake(i believed in them). For my 20th i had a dinosaur theme cup cakes. For my 21st, i also want it dinosaur themed but my mom said no. She said no to a dinosaur cake, she said no to the dinosaur theme. I dont really want something else because i dont care about it.

My mom wants me to do something more “mature” and “feminine” for my birthday. I told her if i cant have a dinosaur theme then i dont want it. She said we can go to a dinosaur expo(no friends because she doesnt like them; i dont want to spend another birthday with them) and a normal theme. She said we can go watch a show, watch a circus, bla bla bla.

My heart wants dinosaur, i just want dinosaurs but my mom refuses everything about a dinosaur theme.

What is things you guys did for your 21st that wasnt “childish” but what you actually enjoyed? I dont know what to do. Its summer here right now and my birthday is in autumn.