No, learn how to listen to your body. Heart rate, temperature are side effects in response to an emotional block (e.g. anxiety, fear of failure, fear of rejection, fear of the unknown).
We have been taught a giant lie that the head is separate, reigning over the “dumb” body. “I think therefore I am” is a load of bull, or a delusion. Your body is your subconscious, your stomach your primitive brain. Your body is chock-full of hard-learned lessons, all delivered to you subconsciously as instincts. Don’t ignore these instincts. We are animalistic creatures, heavily driven by instinct, and rightly so. To discard your instincts is actually irrational!
Observe what your body is telling you. Why is there anxiety? Think to a physical manifestation of your anxiety. Is it tightness in your chest or a lump in your throat, where do you feel that anxiety? Observe it. Do not rationalize it, do not explain it, do not deconstruct it, do not jump to any conclusions. The moment you reach to touch it with your fingers of reason, the truth (body instinct) will slip away. That’s why you just have to observe, non-judgementally.
As you observe and think more about the physical manifestation of your anxiety, see what thoughts and reasons rise up. The more in touch you get with your body, the less information you will be throwing out.
You don’t need external devices to tell you how you are feeling for productivity potential, you just need to A) accept that observing subconscious reactions is a huge source of information, B) your gut feel is correct, but it takes time to process and understand what the gut is telling you, and C) it will take time to get in touch with all your body.
Urgent but simple — have you considered how much of an emotional toll that takes on you? No wonder that can put you into a state where you feel maybe knocked off rails, or some kind of self criticism starts up and you’re beating yourself up for the root cause of urgent task or you’re lamenting the team situation that got you there. These are heavy background burdens, though they may be emotional, are still background threads your brain gives slices to. Now your brain scheduler has less brainpower available for your complex task. Another way to put it is: They are clouds in your heads sky, obscuring the sun of creativity and productivity.
Learn to feel the productivity window by feel, by gut. The same gut feeling will also tell you when to stop. Procrastination often involves avoidance of something, for whatever reason. The trick is to observe what you are avoiding and what feelings are there when you think about this avoidance.