It's all good, I do it all the time. :lol:
Long zoom, like a telephoto? If so, the 55-250 (IS mk II is good, the STM version is even better) will definitely be the best bang for your buck. And they'll match your 18-55 lens nicely.
There are a couple other options, the 75-300, and the 70-300. Which makes it really confusing haha. The 70-300 is good, but more expensive and heavier. The 75-300 is total shit - just get the 55-250 instead, it's much better in every way.
If you want a wide zoom, get the new Canon 10-18mm STM. It's ridiculously wide, and it makes a nice trio with the other kit zooms (10-18, 18-55, 55-250). It's new, and the cheapest ultra wide zoom available, and it's great.