It is a challenge to be a petite model. But there is a lot of opportunity if you stay driven! A lot of the success you will find will be find through yourself and once you accept that you will find reason to think beyond the typical model box and standards.
The Tools aren't just The Internet and The Photographers. The Biggest TOOL is you, and the research you do, the networking, the pitching,selling and marketing of yourself as a model.
Also I wouldn't say you are a petite model in a bad way.
For example refrain from these sentences:
" I know I am so short..."
" I don't know if I can model."
" I know I am petite."
"...I am a good model for a short model."
" I don't know if I should submit to an agent, I am so short."
Instead pronounce your traits...great eyes, hair, skin tone, energy, great at posing, at conceptualizing ideas, your curves, your proportioned body not your short body.
Sometimes simply being on time and easy to work with will get you the job, or opportunity.
Focus on who you are beyond your height and so will everyone else.