Hello TVR and yay for your first grow! To answer your question, yes, it looks like you did a fine job and it looks like the 2 new branches are doing well! Those little growth tips are what will be the two new 'main' colas.
Now for some tips:
- You mentioned that you topped at 9-10 weeks...usually you'll top a couple of weeks into veg, typically waiting until they have 6 nodes, then topping above the 4th or 5th node. This will happen when they're still really short, definitely under a foot, usually mine are closer to 6-8 inches. This helps to save a LOT of time (veg is usually about 4-6 weeks, my runs typically get flipped to flower after about 35 days)
- By topping much earlier, your plants can put its energy into growing bushy as well as to growing out those 2 new branches you created. You then have time to top again if you feel like it.
- If your plants are 3 feet tall, how many nodes were there? That's another reason to top when it is younger - it saves the plant from putting energy and time into vegetative growth that will just be removed.
- Now for the big one: Whenever you're doing something with cannabis plants, always ask yourself if you know 'why'. In this instance, we top because it keeps the plant shorter (so we have more space to move lights up or down in indoor grows without running out of room), and it increases yields (more colas = more buds). Both of those, it seems like you understand, so good for you! But let's take that a step further - should you top the two new growth tips as they grow? What about the secondary branches? The answer is: it's up to you! By having more colas, you increase the yield (up to a point) but each individual cola is a little smaller than if you didn't top. Start with the end in mind....do you want a few big photo worthy colas? Or would you rather have more but smaller colas with an increased yield? Or do you just want to experiment and see how the plant reacts? No wrong answer, just showing why the 'why' is important.
It looks like you've been taking great care of your plant from the photo you provided, so keep up the good work and keep us posted!