I agree with everyone so far.... those phrases could be considered modifying factors, or context. You could also count "on exertion" or "on standing" as Timing... that's when the chief complaint occurs.
There are many things that you could count as Timing, Modifying Factors, or Context. There are many things that you could consider to be Severity or Quality (patient fell on his elbow, states his entire arm is throbbing.)
To answer your question, you could certainly argue that those are modifying factors. Those are things that make the chief complaint better or worse. You could count them as other HPI elements as well (context or timing for example) but as long as you count it once you should end up with roughly the same HPI score as anyone else.
When you've been auditing charts for a while and you become proficient at it, you will be able to mentally scan a note and identify phrases that can count as more than 1 element, make a mental note of it, then you continue reading the history and identify other elements. At the end, you can go back to those 'wild cards' and score it in the most beneficial way possible. That way instead of marking it down as a modifying factor, and then later in the HPI they mentioned that the pain resolved with Tylenol... you could count it as Timing so you get credit for both HPI elements.
