No worries, if you dont care about having the BEST you can do a few things to shorten your time. 1st you can flip to 12h/12h cycle any time you want. There are people that do it from seed. Thus, you dont count a vegetation time so you take from 2 to 4 weeks out of the process. Good light is always helpful, need cheap alternatives? Get some compactfluorescent bulbs daylight 6500k for vegetation if you are going to do it or Soft White 2700k for Flowering. KEEP IN MIND that if you flower your girl from seed or early she will not reach full size or potential, but you need weed right? Also, companies put a number of weeks in their seeds to be ready, you can always cut harvest a week before, this will probably give you a more mental high with harsher taste, but I guess that is way better than your fiance's mom cursing at you. A good combination of nutrients always helps. Of course temperature, humidity, Ph, many other things will play an important role on the growth of your plant but you should be ok for now. Cheers for the people that screw our grows like your moms fiance, they will understand one day whats this all about.