Thanks! For a few years. I was enjoying the leaf structures, but this year, it bloomed! What a nice surprise :) Is it considered invasive?

No.

Most of the shrub dogwoods you would see in Quebec will be natives. Successful, yes...invasive, no.

Even if your dogwood is one of the European species, they are so similar to the North American species that some consider them varieties rather than distinct species. They also don't appear to have a competitive advantage over the native dogwood species so, not invasive there either.

If the leaves are opposite on the stem it is most likely a shrub. If they are alternate, it is most likely a small tree, pagoda dogwood, Cornus alternifolia.

Looks like pagoda dogwood -- here's mine:

And another one:

beng12 - that is exactly it! Thanks so much :)