Hi Matthew! Nice tattoo -- very colourful! As for hidden songs, I'll have a go!
Is that a dove with an olive branch, as in: "Lift me like and olive branch and be my homeward dove", from Dance me to the End of Love?
Is that a cross on his lapel, as in: "I pinned an iron cross to my lapel," from Memories
Is that a tear in the fabric on his shoulder letting in the rays of the sun, as in: "There is a crack in everything, that's how the light gets in", from Anthem
And, as for that big red blob, does it represent: "Your private life will suddenly explode," from The Future
Do let us know, would you?