Why the hell can't he slow down a little for you? Is he that immature that he has to have everything he wants right now, no delays and no negotiations? It sounds to me like he's the one not ready for poly. It takes a lot of empathy for your partner and a lot of patience to do poly responsibly, and he's not showing any of those things. What you're asking for, foreknowledge of dates for example, is *not* unreasonable.
And what's up with him pushing you into new sexual situations so quickly? Is this just a kink for him? Again, by not moving at your pace he's showing a lack of respect.
Parents sometimes take a while to come around. Your mom will almost certainly change her mind over time when she sees the loving, strong role he plays as a partner, father, amd supporter... *if* he can learn a little more care with his actions, that is.
Me, 30ish bi female, been doing solo poly for roughly 5 years. Gia, Clay, and Pike, my partners. Davis, ex/friend/"it's complicated." Eric, Gia's husband. Bee, Gia and Eric's toddler.