I work in construction and also have a sinus cold and at times when I blow my nose I bleed out clots of blood and it bleeds alot. What could be wrong?

Many causes. Although the most common cause is a broken blood vessel from a sinus infection, there are other causes including tumors and various diseases. Since you are having so much bleeding you should see a physician and if a general physician cannot identify the cause then an Ear, Nose and Throat specialist.