Fertilizer probably isn't the problem. Is it container grown? Inside or outside?

Water (too much), sun (too little), and plant not hardened off before locating it outside would top my list of problems for new plants, not fertilizer.

FataMorgana

I am growing it outside in a fairly big pot considering it is a small plant at the moment. And its getting real close to 40 C / 104 F

Quite possibly your basil was grown in a green house and needs hardening off to the incredible high temperatures you're getting down there at the moment. I'd shade it if possible. Fertiliser is way down on the list of likely problems, as Fatamorgana said.

Thank you all :)