Is the following acceptable: was expecting + if I hadn't had

I sent an email recently to a hotel where I'm going to stay, but I got a flight cancelation. Here's a passage from my email,

I had my flight canceled today, I was expecting to arrive at the hotel in time for the checking, if I hadn't had this cancelation…"

My question is whether I can say

I was expecting… if I hadn't had…

Is this construction grammatically correct or acceptable? Or maybe I should've used something like, …would have expected...

Any help would be appreciated

There's a tense issue and there's a word choice problem.

Your second thought was correct. The phrase if I hadn't VERBed is a past conditional, so requires I would have VERBed. For example, If I hadn't missed my flight, I would have arrived this evening.

But this makes the verb following I would have hypothetical and the expecting you were doing actually happened. It was not hypothetical, it was real. Thus this structure does not work.

If you want to keep if it hadn't happened, you need a different hypothetical action, e.g. I would have arrived at the hotel in time for check-in [not "checking"] if the flight hadn't been canceled.

Or, if you want to keep expected, the mood of the second part of the sentence needs to change, e.g. I was expecting to arrive at the hotel in time for check-in, but the flight was canceled.