I had the same thing on my first grow. Only hydro. I got 4 OZ's trimmed bud driied. Killer shit too. Northerns are a good one to start with. Remember you are only lighting the top 1/3 rd of the plant. You need mylar and side lights to increase yeild. I started bloom at 1 foot and ended at 3 foot. When you go to bloom the plants will double or triple in size. If you only have top lighting you should flower at 4 or 5 sets of true leaves. You will get the same thing. Inside you grow short plant to use as much light as you can. 2 feet of my plants were wasted just big stems. Hope this helps.