Thoughts on not having birthday parties?

I need opinions. What is everyone’s stance on birthday parties? My daughter is turning three next week and I really don’t want to do a birthday party but I don’t know what else I could do. I’m super antisocial and I’m 8 months pregnant and exhausted so I want to avoid inviting a ton of people to celebrate, is that selfish? What is a fun cheap alternative to a birthday party that would still be memorable and exciting?