Lisa - Thank you so much for posting, and I'm glad that you've led yourself to this forum for help.  Please realize that regardless of whether a person is "sniffing" or "huffing", ALL methods of inhaling fumes or chemical vapors are both dangerous and destructive. 

Some people who crave the smell of chemical substances such as nail polish may have an iron deficiency (anemia).  Please make an appointment with your family doctor to get a blood test.  If the test results are positive for anemia, your doctor may recommend iron supplements.  Please, however, do NOT take iron pills until getting the results of the blood test and being directed to take them as too much iron in the blood may result in liver (the largest internal organ) damage or kidney damage.

This site has a listing of counseling and treatment programs led by certified addiction counselors, and some centers may have state and/or county funding for those without health insurance:  http://findtreatment.samhsa.gov and can click one's state of residence on the map and continue with the search.

nooria91 - I'm so glad that you've found the information that I'd posted to be very helpful.  Hoping that you use those resources to help you in your recovery.  Field experts have referred to those who stop using drugs or alcohol (but in this instance, actual POISONS) on their own as a "dry drunk" since they haven't dealt with the issues that may have led them to want to self-medicate in the first place.  It's best to get into some sort of a program such as counseling and/or 12-step meetings.

You obviously have a lot going for you with wanting to attend medical school, and stopping the inhalant use can only strengthen your chances of leading a productive and prosperous life.