I woke up this morning feeling fine, but discovered blood leaking out of my penis. it continued for two hours, slowly leaking, then stopped. any idea?

Evaluation: I suggest to make apt with Drs ASAP for evaluation. If you have history of kidney stones you need urologist. Otherwise you can start with family doctor.

Trauma? Stone?: Presumbably you haven't had a straddle injury, i.e. overt trauma to the perineum (between scrotum and anus). However, milder trauma can cause this, like trail biking, horseback riding, etc. Kidney or bladder stones could do this as well. See a doctor.