How much can you afford? What are you thinking of majoring in?
I noticed on another thread that you are a dual US/Canadian citizen, applying from the US. As such you are going to find that by US standards university is VERY reasonably priced in Canada, and that with your stats you should be in good shape at pretty much any university in Canada. I think that you can relax and get some sleep.
We didn’t qualify for need based aid in Canada. In our experience merit aid was awarded just based on the regular application. However, at Canadian schools (unlike US schools) we found out about merit awards quite a bit later than we got admissions results. As such if you are applying now to Canadian schools you might get acceptance letters relatively quickly (particularly given your excellent stats) but you might not find out about merit aid for quite a while. Thus I think that you will need some patience in terms of waiting to see what it will cost. Also, you might have to specifically ask McGill about “Canadian born abroad” tuition to see if you qualify.