You have the power, but you also have to practice not just expect for it to happen. Do you understand magic basics, because maybe just focusing on making a spell without knowing much of how it works could be a cause of why you aren't getting positive results.
Anyone and everyone can cast spells.
Meditate, practice visualization, and learn to balance your chakras, those are good first steps to take to casting spells.
Of course there are more basics involved, but those are the building blocks.
Also remember you must believe the spell will work, understand the spell you're using, and you must want the spell to work.