Are there different levels of heaven and hell?
The short answer
"Levels" reflects Dante's imagery more than the Church's language; the proper term is "degrees." The blessed see God more or less perfectly according to their merits, and the damned suffer unequally according to their guilt.
"Degrees," not "levels"
Talk of "levels" of heaven and hell echoes Dante's Divine Comedy more than Church language. The right word is "degrees" of perfection or punishment.
Heaven
Ludwig Ott's Fundamentals of Catholic Dogma explains that the perfection of the beatific vision granted to the just is proportioned to their merits. The Council of Florence (1439) declared that the perfectly just see the Triune God as he is, but one more perfectly than another according to their merits, and the Council of Trent defined that the justified merit an increase of heavenly glory by good works. Scriptural support: Matthew 16:27; 1 Corinthians 3:8; 2 Corinthians 9:6; 1 Corinthians 15:41.
Hell
The punishment of the damned is proportioned to each one's guilt. The councils of Lyons and Florence declared that the damned are punished unequally, probably meaning not only a difference between punishment for original and personal sin but different degrees for personal sins (cf. Matthew 11:22; Luke 20:47). St. Augustine taught that the lot of some of the damned will be more bearable than that of others, since justice requires the punishment to match the guilt.