Setback?

I did speedwork Wednesday in my new Saucony shoes...I don't know what did it, but I am now hobbling along, even walking. It's my shins and calves. There are knots in my calves and shin splints. Lovely. I have no idea which did the damage, the speedwork or new shoes, or if it was a combination of the two. I'm supposed to run 3 miles in the morning, but I barely made the grocery store walking this morning. So, the question is...take the day off? walk/run what I can? run anyway? Hmmm....