Please Help. Im A Rookie

[tripper]

I had a neighbor take care of my plant that's in the forth week in flowering stage and when i got back today the plant looked like it wasn't watered enough. It had allot of dry leafs even on the top of plant and many yellow dying leafs on bottom. it wasn't like that when i left. I was told that it was very hot while i was gone. I'm wondering if may be i'm using the wrong fertilizer at this stage i'm using this Grow More Super Bloomer 15-30-15 that i picked up at an Armstrong nursery. Is this part of the problem or was it from the stress of the insufficient water?