Didn't run for a week

I didn't run since last saturday. This week would have been suppose to be Week 8 (or more another take on week 8), but I kept telling myself that it's to hot (over 30 degrees C the whole week) or that I'm to tired or have a headache etc all week.

Today is the first day that it's cloudy and only around 25 degrees and my head tells me that I should go out again. But then I'm scared.. I haven't completed week 8 and am scared I won't even manage 20 minutes, yet alone 28.

Why was I so excited about the runs early in the programme and now i can barely get myself to go outside? I need my motivation back