Here is the quote relating to Romeo's shame:
"O sweet Juliet,/ Thy beauty hath made me effeminate/And in my temper softened valour's steel."
Readers could also say that Romeo is not only shamed by his "effeminate" behavior, but also by giving into his passion. In one of his most famous quotes, Romeo announces:
"O, I am fortune's fool!"
This is after he has killed Tybalt. This exclamation demonstrates Romeo's acknowledgment that he has behaved without thinking, allowing others and situations to dictate his actions, and thus leading to his own downfall.