What does the Torah mean when it describes the seven years as "Yamim Achadim" (which seemingly clashes with human nature)?
Rashi: Refer to 29:18:1:1.
Riva #2: After he finished working, it felt that it was a small toil, for he loved her so much. 3
Bechor Shor: This explains why Yakov did not suggest a shorter time. He thought that he was underpaying!
Which is why the Torah adds "in his love for her" - because love causes a person to act and to think irrationally (Seforno).
Pane'ach Raza: However, while working, surely it felt like a long time.