Good for you, and keep it up - just finding a workout group or running buddies is a great investment for encouraging you to stick with it. Plus the ROI - low blood pressure, heart health, and so on - is almost infinite given the low cost of entry.
Joint damage is not really statistically correlated with long distance running, and anyone targeting a sub 20 minute 5k is going to have their weight and form so dialed in, it probably is barely a risk at all.
The other thing is that if you dont regularly change your running shoes, you will absolutely hurt yourself. I get knee pain if I don't swap out my shoes every 250 miles or 3 months.