Hm, I think they look good, and that's fairly normal for flowers on new plants. The flower stems are usually quite long, and after flowering is finished (or when you harvest your flowers for sachets) you should cut them off right above the foliage.
Here's a picture of the purple variety of angustifolia, and it also has very long stems, but there are so many of them it looks great.
English Lavender (Lavandula angustifolia)
You shouldn't prune those baby plants this year, either. Give them a chance to grow into the nice little bushes they want to be. They're going to look really good by the end of the summer, I'll predict.
Next year it won't look nearly so odd when the long flower stems appear on bigger plants. I think you might want to start pruning for shape next year in the fall 2016. After that, they will bloom generously like the ones in the picture above.
