I rejected him but I can't stop thinking about him! Is this normal?

I rejected a really nice shyer guy the other week, he said e wanted to remain friends and so did I and we talked through text for a few days. He asked to hang out a couple of times and I wanted to but can't as am seeing this other guy and also I am going to college soon. I have started ignoring his texts so as not to encourage him but I literally can't stop thinking about him! He sent me a text yesterday and apologised if he did something to upset me. Is this situation normal and what should I do.
Normal/I think aour guys I've rejected
Not normal/i never think about guys I've rejected
Other/see result
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+1 y
Should I continue to ignore him?
I rejected him but I can't stop thinking about him! Is this normal?
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