Do you know how to run? It seemed like a stupid question when a coworker asked me that, but I'd been having knee and other joint pain from running. I watched a bunch of YouTube videos on running and read some sites. If you're new to running, I encourage doing the same. I'm not a strong or fast runner, but I like it.
I think they may have a point about the not overdoing it part - you don't want to start off over analyzing your gait and style. It'll be slow at the start while you tweak any weaknesses apparent. My big one was keeping more upright - I had a sprint coach assigned to me for my sport of choice and they got me to keep my chest up, I had a tendency to let it droop when I get more into my stride, probably because it felt natural and I had been doing it that way for years; sort of lazy like. It took me a while to get the mechanisms down after years of doing something a specific way, but if you're relatively new to the whole running thing I bet you'll be loving it in no time!
Looking at a couple now, this one hits all the points I found important for myself: The part starting around 1:40 was especially important for me. I spent a lot of time running more slowly but making sure I didn't over stride and land on my heel. The video hits a lot of other good points, too.