Good evening Nellie.
Happy Birthday! Don't feel you're alone dealing w/these feelings of loss. You had said that this was your first b/day celebration in 30 years. You feel bad because you missed out on these celebrations w/your family and father and friends. You have every right to be feeling sad. I know I certainly felt the same way.
Hormonal changes can really put you in a tailspin. Stress can affect the balance of the hormones also. That's good that you are going to your dr. and sounds good to have a good cry. That's one of the ways your body deals w/a lot of stress and sadness.
Have a good time w/your new friends, Nellie. It takes time to heal.