You can work through that with some practice and strength training.
As you start to climax in her and change your thrusting to what feels best, start kegeling you PC muscles to the rhythm of your ejaculations. Keep kegeling the muscles an the same climax rate, keep thrusting. It’s going to be a slower, gentler thrusting, but stay with it. Pay more attention to her body parts that turn you on. Keep kegeling, and thrusting. Kiss, squeeze, caress, slap, lick, talk dirty. Sexy foreplay while you’re already in there. Keep kegeling, and thrusting. Your attention starts to shift back to how amazing and wet they feel on your cock. Keep kegeling, and thrusting. Your erection will come back up to full strength
Hey, look whose back in the ring to take another swing.
When the valves open to start deflating erection, you’re trying to manually pump blood back in faster than it leaves. Keep it going until your horny resets and valves close.
If you pull out or stop stimulation, your body thinks you’re done with fucking and wants to put your penis away = refractory period. “I came, but I did NOT say I’m finished.” You can keep trying to fill her up with cum until her nose starts to run.
You’ll probably want to try this with a Cockring until you get used to it. They help kinda like a power-lifters weight-belt, it gives your muscles something to flex against so you can flex harder. Plus slow down blood escape.
Not for condom wearing. Methods like Spermicide will need reapplied.