How do I react, do I show jealously?

A guy I work with is a good friend of mine, I’ve asked so we can see each other but hasn’t found to time. Today he said he has a date and it broke me. How do I react to this? I said yea right and he’s like what do you mean yeah right

and I haven’t said anything cause I don’t know what to say

Do I need to tell him I like him?

How do I react, do I show jealously?
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