There is absolutely nothing wrong with your technique. Baby locks should have between 1-3 inches of straight hair at the roots. This straight hair is 100% needed for locks to mature properly.
Think about it objectively, for a second. Locks are a tangled mess of knotted and looped hair, right? But they don't grow out of your scalp as 1 thick strand. That's physically impossible. So the only other thing that can be happening is that each hair still has to grow out of it's respective pore individually, and straight. This means that there will always be some straight hair at the roots that isn't knotted and tangled yet.
That's just fine. In fact it has to happen, like I said, before. Baby locks should have between 1-3 inches of straight hair at the roots. This hair is what loops, knots, and tangles with new growth, creating a new, strong base for your locks. Trying to crochet loose hairs into a lock prevents this from happening. In fact, it forces your roots to thin out and get weak, since all crocheting does is breaks hairs into smaller and smaller pieces. Be crocheting, and therefore breaking, the hairs at the roots, you are weakening his locks, considerably.
As they mature, that section of hair at the roots shrinks to about 1/4 - 1 inches of straight hair. And it locks itself up on its own. There's nothing you should do to try and force this to happen.
His locks are only a few weeks old. he's still about a year away from mature locks. You can't do anything to speed this process up without severely destroying them. If he wants them for more than a few months-a few years, then crocheting is ok to achieve the "look" of locks. But it doesn't create locks. If he wants to have them for years, or life, you need to let them happen naturally.
As for the tips... Again, baby locks should have about 3 inches of straight hair at the tips. And healthy mature locks should have 1-3 inches of straight tips. This is a good thing. Blunted tips may look all neat and tidy, but they are a detriment to locks. Blunt tips hold water longer, making them get waterlogged, and can cause mold/mildew to grow. Wispy, loose tips allow water an easy way to drain out of the lock. This lets the locks dry hours-days faster than ones with blunt tips.
