Random bleeding pinprick mark on my arm, help?

Last night I noticed patches of blood in the crease of my arm and I wiped it off and saw a tiny needle like mark, it was fine then around 20minutes later I went to bed, and it started bleeding again, quite abit, yet I couldn't feel it until it was drying and it doesn't hurt, but my arm does ache abit, and no this isn't a fake question, I do not inject myself with anything. Could it be a bug bite? If so, why did it bleed so much?