In my opinion both of your shen builds up there aren't good.
START: 2x rejuvenation bead, potion, sight ward
CORE ITEMS: basic boots ---> Warmog's armor ---> ninja/mercury's ---> sunfire cape ---> rylai's crystal scepter
SITUANTIONAL ITEMS: Randuin's Omen, Spirit visage, Guardian Angel, Twin shadows, Aegis/Runic, Wit's end, Frozen Mallet, Abyssal Scepter
There are other viable items as well, but it all depends on the game.
I personally don't use Wit's end or frozen mallet ever on shen. If I need magic resistance I'll get plenty with spirit visage, abyssal, runic or other mr items. I rarely build twin shadows, but can be useful when chasing down enemies with allies behind you.
Quick guide on how to play shen:
Early game you need to farm a lot while trying to harass your opponent. If your enemy has high sustain or is just poking back 10 times harder you should stay safe until the jungler helps you.
Once you hit lvl 6 start watching the map often. You'll see all your allies life bars on the left of the screen. Keep looking at it to stay updated with what's going on. Do not miss a teamfight as shen.
Mid to late game you either stick with your team or split push while your team pushes another lane. Be careful to not get caught by the enemy team though. Do not split push if you lack your ultimate. Teleport is always a good summoner spell on shen. You can do an early gank bottom lane from a ward behind them by teleporting to it and taunting them. You should ask the jungler to hold the top lane first if he's nearby.
Lastly... Do not miss a teamfight
