I told him I’m in love with him and he said “same”

So I was texting my boyfriend and I thought he felt the same as me so just to be sweet/cute I was like, “HEY I’m in love with you” (something he already knows) and all he said was “haha same” oh? Okay..

Should I not be a little sad? I wasn’t expecting such a dull reaction.

Edit: it was not said the first time over text! We have already said it before and established this in person. That is why I texted “in love with you” to be cute. Jesus people