わたしが前をよく見てなかったから、出会い頭にぶつかっちゃって。小川くんは悪くないわ。

、。。

I wasn't looking where I was going, so we collided at the corner. It's not Ogawa-kun's fault.

Literal

I [subject-が] ahead [object-を] well looking-not-was [reason-から], head-on [to-に] bumped-[contraction-ちゃって]. Ogawa-kun [topic-は] not-bad [feminine-わ].

出会い頭に ('head-on, at the moment of meeting') describes a collision at a blind corner — a common accident pattern. ぶつかっちゃって contracts ぶつかってしまって, with the ~ちゃう conveying regret. よく見てなかった ('wasn't looking carefully') is the casual negative past of continuous. The speaker takes full blame with わたしが...から, then explicitly clears the other person.