Itching In Calves, Red Dots, Bleeding, Puffy Veins When Going Near Bermuda Grass

Thank you, I live in Phoenix. If I go out on back patio ( we have Bermuda grass and a couple of gardens with herbs and veggies growing) in shorts to barbecue just sit ,My calves get super itchy with tiny red dots and if I scratch , even lightly, I get long red lines and my skin bleeds . When this occurs, my veins get very puffed up and there are usually a couple of blood dots the size of pinpricks. I am a male in pretty good shape 61 years old. Thanks in advance, Paul