Suppose to be on week 5 run 2 today. Woke up in the night and could hardly move without pain in my back, it’s the same this morning, so disappointed. The only thing I did differently yesterday was use a physio roller I bought, think this is what’s done my lower back pain to come. Has anyone else used one of these and developed back pain? No running for me today, have to let my running buddy down which I hate to do.