I know my 21st is not something you'd want to do- being that your a new Mom and breastfeeding- but it's funny, so I'll share
I had moved out of my parents house at 20- moved 2hrs away and lived with my B/F and his sister. So we all went out- a couple other friends included to a bar/club at a Hotel. My Dad wanted to visit me that weekend- so I said fine- thinking he could just stay in while me and my friends went out. He'd have his "father time" during the day- but my friend decided to ask him to join us!! I was a bit hesitant- but didn't want to be rude... so I said, "hey, why not? Come out!"- so he did. And yes, I spent my 21st bday at a bar with my friends and my DAD who actually bought us all a shot- AND ended up on the dance floor with all of us at one point!
I'm glad I have that memory now!
Since that is prob not your idea of fun right now
Just have a quiet night celebrating with the people in your life -- please don't feel down. I know that easy for me to say-- but, at the end of the day, it's not about what you do, but the people you do it with. And I'm sure just a hug from my LO would be present enough these days! Besides- you can always plan something bigger later down the road with friends once they are in town and you are no longer breast feeding... there is ALWAYS time to plan a girls night out one day soon!
You could always tell OH your going to a nice restaurant (don't wait for him to plan, just make the plans!)- and go out in style all dressed up and have a drink- something fun! Then go home, get in your comfies and enjoy your family...
Happy Birthday!