Is it normal my freind keeps harrasing me about this?

I have this old friend that I have not seen since graduating high-school. They asked if I liked them and when they did not get a satisfying enough answer asked if I ever liked them in the past and keeps rephrasing the question. I asked them why they care so much and they said its no big deal they were curious but if its not important I don't understand why they wont just drop the issue.