What Causes Tiny Red Dot On Arm That Is Bleeding?

Hey. Well I had a tiny little red dot in my arm. In the muscle area to be specific. I pinched it because I assumed it would be a pimple. It started bleeding and got swollen. I would flex my muscle and blood would come out again. I would slightly pressed the swollen part and blood immediately come out. Is that bad? I am kinda scared about this. I would really appriciate your anyone's response.