

At this age you are used to your body just keeping up, so when an ache starts getting between you and the things you do, the gym, five-a-side, being on your feet all evening, seeing mates, it is genuinely annoying. Time with friends and staying active are a big part of life right now, and missing out on them is not something you want to make a habit of. The frustrating bit is that the two obvious responses, push through it or stop altogether, are often the two that help least.
When something hurts, the instinct is usually one of two extremes. Grit your teeth and carry on exactly as before, or drop the activity completely until it feels better. Powering through tends to keep aggravating whatever is sore, so it never gets a chance to settle. Going fully still, on the other hand, often leaves you stiffer and no closer to getting back to it. Most discomfort settles fastest somewhere in the middle, where you keep moving but ease off the bits that wind it up.
You rarely have to choose between doing something at full tilt and not at all. If a run is too much, a walk or a swim keeps you moving without the same pounding. If a full gym session flares things up, you could train the parts that feel fine and go lighter on the rest. If a long night on your feet is too much, you could sit for part of it. Keeping the thing you enjoy in a slightly adjusted form beats parking it completely and waiting.
Because so much of life at this age happens with other people, it is worth protecting that even when you are sore. You could suggest something gentler when it is your turn to pick, meet for a walk or food rather than something that leaves you aching, or go along and take it easy rather than sitting the whole thing out. Being upfront with friends helps, most would far rather flex the plan than lose you from it, and staying connected tends to lift your mood in a way that helps everything feel more manageable.
Easing off is not the same as stopping. When something is grumbling, you could dial the intensity down for a week or two, keep gently moving, and build back up as it settles rather than going from nothing to full pelt. Gentle movement usually helps discomfort settle faster than complete rest, so the aim is to keep ticking over at a level that feels comfortable, not to shut everything down and wait it out.
You should not have to put your life on hold to let an ache settle, and at this age you really do not need to. Keeping things moving in a slightly gentler form is usually what gets you back to the full version soonest.