I had the same problem when I started raw paleo. I got so skinny I looked sick.
I had already lost a ton of weight (80 pounds) and was comfortable at the weight I was thanks to The Specific Carbohydrate DIet.
But when I started raw paleo I got extremely thin. So thin people would tell me I need to stop trying to lose weight, and I look sick. It actually (now that I think about it), probably made some people think I was obsessed with losing weight. I was eating a ridiculously strict diet, and everyone thought it was to lose weight. Not to be healthier. Go figure (Americans... {no offense}).
Any way. Looking back now, I realize my problem was not getting enough fat, protein and calories.
You sound like you're very active. So you probably need more calories than the average person.
I recommend an app on your phone, or online that can track calories consumed (food) and calories burned (exercise).
If I had tracked how many calories I was eating back then.. Well I was eating about 120 grams of carbs. And like 3 5-6 oz servings of meat. Realistically my calorie consumption was probably under 1300.
I suggest getting a hold of good fat sources. Look for places that sell raw beef fat, or suet. Most places that sell GF beef will also sell GF beef fat or suet.
Here's the nutrition analysis for 1 oz of beef fat and 1 oz of suet.
Suet -
http://nutritiondata.self.com/facts/beef-products/3478/21 oz = 239 calories
Raw beef fat -
http://nutritiondata.self.com/facts/beef-products/3203/21 oz = 189 calories
Using suet or raw beef fat, you can EASILY reach the amount of calories you need daily.
But don't underestimate the amount of protein you need, you're exercising a lot.
Here's a protein calculator that will factor in your height, weight, types and intensity of exercise.
http://www.gnclivewell.com/proteinnumber/Calculate your calories starting with getting the right amount of protein. Then factor in carbs. I personally think you need carbs with all the exercise you're doing, even though many here are anti-carb. Then get the rest of your calories from fat.
Using fitday, or one of those programs I mentioned that track calories will help you.