Need advice

My plant is growing tall and skiny, now of course i need to state that this plant has grown 100% under a normal bulb until yesterday i got a 400w mh light, i have never used nutrients until yesterday also i gave it some 15-30-15 now i know its not the best nutrients for veg stage but its all i have and i think its better then nothing?

What i am wondering and need advice is how do i get the plant to get bushier because it is a feminized super lemon haze that i would like to use to make clones but right now there are hardely any to take.
could i tie the 2 main stems sideways so it stops growing in height?
should i stop giving it 15-30-15 and just give it no nutrients?
also there are brown spots on 2-3 leaves which i wonder if i should just not care?

Yes tie them down sideways

Super crop in multiple places and create a whirlwind type appearance where branches run horizontally.
That's the best way I can describe it.
Use stakes or canes to keep it in that position and the new growth will grow up from each node and give you lots of cloning sites.

You will see more clone-able shoots in two weeks with the new light

replanted it and tied it down hope i see progress soon

starting to look better would like a different shape if you know what i mean, more like a bush and less of a Y shape

tied it up make it bushier