Is the word fiquei the same in Brazilian and European Portuguese?

No

While the spelling and grammatical conjugation of "fiquei" (the first-person singular past tense of ficar) are identical in both varieties, there are differences in typical usage and collocations. In Brazil, "ficar" is used extensively to describe temporary emotional or physical states and is the standard term for casual romantic encounters ("ficar com alguém"). In Portugal, while the verb is used similarly for "staying" or "remaining," the surrounding vocabulary and the way people express specific social situations or sudden changes in state often rely on different verbs (such as perceber instead of entender) or different idiomatic expressions. Additionally, the pronunciation differs: Brazilians pronounce the vowels more clearly and openly, whereas Portuguese speakers tend to reduce or "swallow" unstressed vowels, making the word sound more compressed.

Brazilian Portuguese Examples:

1. Eu fiquei muito feliz com o seu presente. (I was very happy with your gift.)
2. Eu fiquei com o Lucas na festa ontem. (I hooked up with Lucas at the party yesterday.)
3. Eu fiquei sem entender o que aconteceu. (I was left not understanding what happened.)
4. Eu fiquei de bobeira esperando o ônibus. (I was just idling/waiting around for the bus.)
5. Eu fiquei com muito medo do barulho. (I was very afraid of the noise.)

European Portuguese Examples:

1. Eu fiquei muito contente com o seu presente. (I was very happy with your gift.)
2. Eu estive a sair com o Lucas na festa ontem. (I was going out/seeing Lucas at the party yesterday.)
3. Eu não percebi o que aconteceu. (I didn't understand what happened.)
4. Eu fiquei à espera do autocarro. (I was waiting for the bus.)
5. Eu fiquei com um grande receio do barulho. (I was very fearful/apprehensive of the noise.)