I'm 3.5 months post op. By looking at my picture, am I going to get good density after 6/7 months? (Photo)

The hair goes through it's intrinsic hair cycle and will start to grow after  three months and may take up to 18 months for also the hair to grow in.  There is no way to tell at which stage the hair once it is implanted, you just need to be patient. And let it go through its process. 

Density after a hair transplant is directly related to the number of hairs transplanted. Predicting growth at this point is impossible. In general, after a transplant hair follicles will reawaken between 2 and 5 months after the procedure. The hairs will continue to reawaken for another 6 months.The hairs initially will be finer in nature and thicken over time. Most patients will achieve full results from their procedure between 10 and 14 months post hair transplant.