I'm still a little shocked on how much I overthought it. I feel like I did it way too soon, but I came out to my Mom tonight. I wasn't ready to do it, but she cornered me. It was the most we've talked in about a week, she was worried about how I'd been acting over the past several days. We live together so I was unable to really hide my own emotions. I tried to tell her that I'd had an epiphany recently and that, though it felt right, it scared me. As the conversation continued, she then picked up her phone and said I needed help. Apparently my explanation had led her to believe I'd developed mild schizophrenia. That was when I just closed my eyes and said that this wasn't a mental condition, it was a "coming out thing". I tried to avoid her probing but when she said that she'd accept me even if I were gay, stupid me just had to correct her. I told her I wasn't gay and just about left the room. She was quiet for a minute before asking if this was like my trans friend's situation. I didn't expect to cry when I nodded.
I was really scared of her silence until she turned supportive. At the same time, she tried to see if I actually was trans. Considering how she's a nurse with a psychology minor, she really read into me before she looked all confused. She then said that I'd never shown signs of Gender Dysphoria. I tried to call her on that, but apparently all the memories I brought up had meant more to me than her. Even my "funks" seemed normal to her, though I had to point out that they were large periods of denial and depression for me. She just thought it was seasonal depression.
In terms of attitude, she was mostly neutral. I think she believes she's calling a bluff, but at the same time she seemed eager to support me. She pointed out that I can actually get a Gender Counselor through certain Employee Assistance Programs and then handed me a couple numbers to call in my step-dad's company (I'm still his dependent). At first I thought she was trying to push things along, but she told me to just try to get to a normal state of mind so I can think more clearly (I really had trouble explaining things to her). She also promised to keep this a secret from the rest of the family.
I can't believe I'd overthought this so much. It probably would have gone smoother had it been more on my terms, but it went so much better than I'd thought it would... I'm still nervous though, because I'm not sure a part of her believes me.