Actually.. No.
According to Merriam-Webster,
Irony: the use of words to express something other than and especially the opposite of the literal meaning.
That is exactly what I did. Your example is also correct, and would have been completely IF I had repped and not said anything.
However, sarcasm is quite different. Again, from Merriam-Webster,
Sarcasm: a sharp and often satirical or ironic utterance designed to cut or give pain.
As you can see, sarcasm does not describe my post at all.
People tend to confuse irony with sarcasm much of the time. Sarcasm is usually biting, but irony is softer.
I would say sarcasm is a lower form of irony. (As read in the definition)
And also, Irony can also be quite offensive too; but more sophistical and indirect. Like an insult you'd only understand after one leaves the room
