nutrient question!?

hey.
Im in 4th week of flower, the buds do not look that big but I was thinking about getting some "big bud" from advanced nutrients. I have not use nutrients yet, should I buy it? Is it too late? here's some pics so you can get a better ideal.

Welcome to the site catchinzzzs.

I would first go to growfaq link on the top left.

Things to consider:
1)Medium
2)How long it has been since you 1st noticed sex after switching to 12/12.
3)How much longer do you want to flower?
Pics look good so you are doing something right.

I guess I would say go ahead with the bloom nute at 1/4 strentgh that the manuf. recommends.
Then you can increase slowly from there.

I would try molasses as well. 1tsp per gallon.
The molasses was suggested by Videoman awhile back.
I have had very nice results from it.

Happy growing