Question

One can infer that the speaker of "poor fish"

has self-esteem problems.
doesn't like ida.
is a happy person.
had a very troubled youth.

Answer 1

One can infer that the speaker of "Poor Fish" has self-esteem problems.
He thinks he is not good enough, and he is quite shy and self-conscious about his flaws. Only when he meets Ida, who falls in love with him, does he manage to gain some confidence because she is constantly reminding him of the fact that he is great.