@lydiabaggins What I do in this situation, is take a look at what the OSM map looks like.
If it is accurate, then it might be a GPS issue on your device. Since you mentioned Runkeeper, I think that means phone, and I have found phone GPS to be a little funky sometimes.
If the map is not accurate in OSM, OSM can be edited so that the road is shown correctly. In this case, a city update (here on CS), will pick up the change and reprocess your data.
For info on editing OSM, you can see this: OSM Basics
Oh, OSM lets you upload GPS traces, and that makes making things more accurate super easy.
Hope this helps, Eric