If you think you may suffer from a gluten allergy, such as coeliac disease, it's best to have yourself tested by a qualified medical professional, rather than self-diagnosing.
Flour contains a high degree of starches, which are complex carbohydrates. It is also likely to have 'flour improvers' added to enhance its keeping qualities. Vitamins, which are lost during the processing, are often added back in artificially to increase the flour's nutritional value. Additionally, plain, all-purpose or soft white flour is usually bleached to make it look more attractive.