I think we are at the same time the best and the worst people to ask for/give advice. The best because most of us have been running for a number of years and have learned a lot; the worst because we don't actually act on what we know! Most of the regulars here walk (or run) along a very thin line between maintaining/improving performance and getting injured. Most of us stray the wrong side of that line at times and that's why at any given time a number of us are crocked.
Artie's has nailed it...………….and after 35 years of running it's good to be reminded of these first principles.
And if you really can’t resist a run, then run as slow as possible. I’ve ran through injuries but speed work is a big no, no.
As mentioned above the key is to differentiate between pain (stop) and tightness (stop or slow down).
Go for a bike ride, swim or walk instead if necessary.