Well that all really depends on you. How much room do you have to grow in? How big do you want your plants? Plants grow about 2x the size when done flowering. Sativas, some of them 3x from the size of veg, you look like you have a indica dom strain so, about 2x. But to answer your question, yea you can flower it now if you want to, or wait and grow it larger.
hope this helps.
-hardroc
thanks everybodyYeah id say give it another few days.. then put it into flowering.