air circulation and exhaust will help. keeping fresh air in there big plus. till you get a handle on things i would not just start throwing nutes in there will do more harm then good.
the nute you have will do just fine. dont use the big bud and final phase together big bud is for weeks like 3 to 6 final phase is for last week or so

might want to look into LST or bending the plant so you have plenty of room for the plants too finish