notadictionary.com
Je l'avoue, je l'ai peut-être secoué un peu trop fort
→ “I admit it, I may have shaken it a little too hard”
Je — I → subject pronoun
l'avoue — admit (present tense, 1st-p. singular of avouer)
je — I → subject pronoun
l'ai — have (auxiliary verb for past tense, 1st-p. singular of avoir)
peut-être — may perhaps → used as an adverb meaning 'perhaps' or 'maybe'
secoué — shaken (past participle of secouer)
un peu — little → here, 'a little' as part of the phrase 'un peu'
trop — too → indicates excess
fort — hard → describes the intensity of shaking