You'll know if you added too much Nitrogen if the buds become leafy, which you'll really notice at some point. I think you're fine....... FYI, my normal process is to continue fertilizing the same as my veg schedule the 1st 2 weeks of flowering, then the next two weeks I do a 50/50 split of veg/flower nutes (I use Botanicare products) and then after a month, a full flower routine. I find if I don't give the plants a lot of N early in flowering, they show deficiencies way too early in flowering and the plants health declines too rapidly for full resin production. Of course, overall flowering time and the strain type come in to play too.......as does light intensity, temps of room, etc.