Same thing happening here, I've found that it really only happens when I do tests straight through. When I drill specific sections, I general go minus what I had been doing at my best. Granted test day entails taking them all back to back, but drilling individual sections has essentially confirmed that it's not my strategies or skills that are wrong, more just psyching myself out!

So, maybe just drill 4 sections, no stress, do well, feel good about it and just remember that if you stick to your guns, you'll be a-okay!