Any ideas as to why my penis elongates (not erects) then twists and leans to the right pointing downwards, immediately after i pee?

Here are some ...: The penis tends to engorge at a full bladder especially at young age; this pee-related erection is common and not clinically significant. Such penile engorgement or erection with a full bladder will de-tumescence soon after voiding, resulting in a limp penis toward the direction of curvature. Remember: No man's penis is "perfectly" straight. So, what you have observed is normal.