You should stop exercising immediately if you experience chest pain or pressure during a workout because it could be a sign of a serious heart problem and you should seek emergency medical attention rather than trying to push through it.
If you suddenly feel dizzy or lightheaded while lifting weights you should stop your workout and sit or lie down somewhere safe If the dizziness is severe keeps coming back or happens with chest pain or difficulty breathing you need urgent medical attention.
If you experience unusual shortness of breath that feels much worse than your normal workout breathing you should stop exercising immediately Severe breathing difficulty especially when accompanied by chest pain or faintness needs emergency medical attention.
If you hit your head while working out and then develop confusion vomiting a severe headache or unusual drowsiness you should seek urgent medical attention Head injuries can be serious even when there is no visible wound.
Feeling slightly tired after a demanding workout is normal but extreme exhaustion that does not improve with rest is different If your energy levels keep dropping or everyday activities become unusually difficult you should take a break and speak with a healthcare professional.
If your breathing becomes difficult and you notice wheezing or tightness in your chest during exercise stop immediately If the symptoms are severe or do not improve quickly seek urgent medical care because breathing problems can become dangerous.
I would not continue exercising with a fever or a significant illness because your body needs time to recover If you have chest discomfort unusual breathlessness or extreme weakness while sick you should avoid training and seek medical advice.