He has been poorly on and off for about 3 weeks. He'll have a temp and be snotty for a couple of days, recover and then a few days later go down with it again. he was very poorly with a high temp of 39.9 for most of the weekend (and that was after calpol), very snotty and coughing. I kept him off school today, but tbh I think he would have been ok there as he's been running around fine. But he has just coughed up quite lumpy bits of mucus which are have a fair bit of blood in. The blood is fresh, bright red. Should I be taking him to the dr's tomorrow or is it most likely to be due to the exertion of coughing? He's never done this before and has no history of resipiratory problems.