YOU SAID:

I hopped into a coffee shop and then my jaw dropped it I saw a girl and some really cool pants

INTO JAPANESE

コーヒーショップに飛び込み、女の子ととてもクールなパンツを見たときは驚きました

BACK INTO ENGLISH

Popped into a coffee shop and was surprised when I saw a girl and some very cool pants

INTO JAPANESE

コーヒーショップに立ち寄ったら、女の子ととても素敵なパンツを見てびっくりしました

BACK INTO ENGLISH

When I stopped by a coffee shop, I was surprised to see a girl and very nice pants

INTO JAPANESE

喫茶店に立ち寄ったら、女の子ととても素敵なパンツを見てびっくりしました

BACK INTO ENGLISH

When I stopped by a coffee shop, I was surprised to see a girl and very nice pants