Hi Jennifer. The best approach is to have your doctor order a blood test of your fatty acid levels. Sadly, most docs don't know about this.
Here is a quick 'primer' on the essential fatty acids (EFAs). They are essential components of the diet because the body cannot make them.
There are 2 types of EFAs: omega-3 and omega-6. (Omega - 9 is made in the body.)
Most people today get too little omega-3 fats in their diet and too much of omega-6 (primarily Arachidonic Acid). Omega-3's are generally 'anti-inflammatory' and omega-6 (the arachidonic acid form) is pro-inflammatory. One type of omega-6 is also anti-inflammatory - it is called GLA - gamma-linoleic acid.
The 3 major forms of omega-3 in foods are: alpha-linolenic acid (ALA), EPA and DHA. Of these 3, EPA and DHA are the most important ones for optimum health. EPA and DHA can be made from ALA (found in linseed oil, for example), but only in very small amounts. Therefore, you want to supplement with EPA and DHA forms of omega-3s - these are found in fish oils.
You may want to add the good form of omega-6 (the GLA) to your supplementation too. This is found in oils such as Borage oil.
Fish oil supplements from Nordic Naturals or Carlson labs are excellent.
Hope this wasn't too complex to be helpful for you. Best wishes.