B Rock, from your reactions it sounds to me like you need to take things down a notch in terms of your sparring intensity. Your goal should be to learn how to do things right, and it sounds like you don't have enough confidence/practice in your skills at the intensity you're sparring at to execute your skills correctly. Bring things down to a speed/intensity where you do feel confident and then slowly build up from there.
Different people have different temperaments, tolerances to stress, pain tolerance levels, and even life experiences which can cause them to respond differently to certain situations. Therefore, the same level of intensity might be just right for one person, way too much for another, or not enough for yet another. The same cookie cutter "you should spend the majority of time training at X intensity..." approach may work great for one individual and horribly for another.
I'd suggest starting out your sparring session at 10% speed/intensity, if that feels fine, go up to 20%. Still fine? Then go up to 30%, and so on until you reach a level of speed/intensity where you start to feel tense, panicky, start to "think" too much, and stop being able to execute your techniques effectively. Then drop back down just below that level. Work in that intensity/speed range for a while until you really start to feel comfortable, and then every now and then test to see if you can ratchet up the intensity and still be able to keep your cool. Eventually over time you will get comfortable at greater and greater intensity levels and eventually be able to go full speed/intensity comfortably.
Once you get to that point, then it's a matter of maintaining your comfort in going full speed, but not doing it too much that it starts to wear down your body or possibly have adverse affects down the road (hard strikes to the head can cause bruising of the brain, which, if done too often can lead to nervous system problems, like Parkinsons, down the road). Even professional coaches like Freddie Roach don't advocate going all out all the time. So no need for someone who isn't a professional fighter to do so IMO.
This is of course also going to require that you find a training partner who is capable of controlling themselves, not ego driven (isn't going to ratchet up the speed/intensity if they get hit or start to "lose"), and comfortable training at or above your level of intensity.