Is this a Jacaranda or a Silk Tree or something else?

Question

Back in March, I bought a baby Jacaranda tree from Ebay. Well, they claimed it was a Jacaranda. Just recently I discovered Silk Trees which look remarkably like the Jacaranda. Everywhere I read, articles said the best way to tell them apart is by their flowers. Well either tree won't flower until a few years old. So is there any other way I can distinguish between the two? Is what I purchased a Jacaranda or a Silk Tree...or even something else? Here's some helpful info which may help identification:

1. I purchased the tree as a tiny little sapling for $10 on Ebay.
2. It was not bare root nor was it grafted. Def grown from seed.
3. The seller was growing them in Florida.
4. I live in Southern Texas.
5. This tree has thrived in my clay soil with only watering once a week.
6. Just came out of a drought too so the tree had no real rain water.
7. The tree grew from about 1 inch tall to over 5 feet in about 6 months!
8. Has one main trunk, though started sprouting a secondary one at ground level

Plethora of pics:

Answer 1

I have a jacaranda, also not flowering yet, which I know to be a jacaranda because it was also planted from a seed. It seems to be pretty easy to sprout these jacaranda seeds, so I would be inclined to believe your e-Bay seller for that reason alone. But also your tree looks just like my J. tree: trunk-dots, fluffy leaves, branches, fast growing, everything.

But. . . Now that you point out the similarity between silk tree (i.e. Albizia julibrissin or "mimosa tree"?) leaves and those of Jacaranda, boy they do look alike, even though not closely related at all. However, here is a "frond" off of my tree

The little "branchlets" (don't know what they're really called) have a single leaflet sticking out at the very tip, and notice the deep groove down the center of each leaflet. Just like in your photos. My end-leaflet looks a little longer than yours though.

I don't have an Albizia silk tree handy, but checking the internet, it looks like they don't have a leaflet at the very tips of the branchlets. So they do look a tiny bit different from the jacaranda.

Invasive silk tree

So I think it truly is what it claims to be - Jacaranda.