My first motorcycle too. Well, I started on a scooter...so you get what I mean.
There is a great motorcycle skills android/iphone app from MCrider. A whole section for emergency stopping and techniques to apply while you're learning. I highly recommend it, in conjunction with a Motorcycle Safety Course...if you haven't done so already.
I was having issues going from neutral into first. I was also coming to a stop at traffic lights, or stop signs, without properly downshifting through the gears, then had the same issue as you. So I did some google rummaging and came upon the "feathering clutch" technique I describe above. Now, along with proper downshifting, I use the technique anytime I go from neutral into first...it's become a habit.
Then you'll get into rev-matching during downshifts, which for me was an epiphany, it makes shifting down through the gears so much smoother when you're at speed. It takes practice, but once you get it, man it really makes a difference and allows you to safely use the engine to help slow you down. It also eliminates back wheel chatter. Anyway, something to look into that I think might help you like it did me.