I feel like a *****? how can I apologize?

Hi, today my bf said hi to this girl and I said 'who's that' and he said...'No one babe' then I went 'she's pretty aint she' and he goes 'nope cuz ur the only girl for me and no other girl will ever as beautiful as you are' and my jaw dropped and I felt like a ***** since I didn't trust him...then he came and grabbed my hand and just kissed me and said he loved me... How can I apologize...we're both 15 if that matters