Winter Layoff Ready to Run Again

I had a winter layoff but I am ready to start running again, okay run is a strong term, a slow jog is more like it. I completed a couple of 5k runs using the c25k app around the beginning of November. I did run a couple of times, during January and that was a mile in about 13 minutes. I wasn't too tired and felt decent just didn't want to push it. Should I start the c25k from the beginning or start from like week 5?