The first thing that sticks out is the lean meat. No reason to go lean if its grass-fed. Minor reason to go lean if it's not (fatty acid ratios that are minimal to begin with). Cuts closer to the bone are often cheaper. Going with bone-in roasts brings in more fat as well as the nutrients from bones and marrow (collagen, gelatin, etc).

At your age I could have written your post. it is striking how similar we are. I wanted to get rid of my migraines and I can understand the lengths it can drive a person to, but be careful, if you go down the exclusion road it'll take you further than you want to go. Better to think "What food am I missing that prevents my migraines?"

For example, milk can worsen acne if your vitamin A is low. Low blood sugar or stressful events can cause a migraine, sugar is needed more in stressful events... etc

Whatever you try eating you need to give it a couple of weeks. The body needs to get used to different food, especially things like milk and eggs. When I started eating milk after a long break (8 years) it took a good couple of weeks for my body to be regular again, until then I was bloated and on and off the toilet.

Try watering down fruit juices if you have a sensitive stomach. It is quite easy to get an additional 500 calories from a 1L bottle of something like freshly squeezed pineapple juice, and it'll cost less than half of what meat would have cost you.

Milk is another fantastic product for bodybuilders. If you can't tolerate it, try goats milk. Work up slowly from a fraction of a cup a day to as much as you like. Keep it whole milk for even more calories. You'll get 700Kcal from 1L of whole milk, 3 cups of instant food.

With regards to adding butter to potatoes or starch - that doesn't work for me. I get indigestion from the combination. I can however eat butter with eggs or meats. It is best if the meat is lean as mixing different animal fats together seems to mess my system up.

-Also consider that it could be vegetables giving you stomach problems -Generally they will bloat and cause you to produce a lot of gas.

Try some almond butter. I aim for 3000-3500cal daily too, and almond butter helps me get there if I fear I'm coming up short. I'm M, 6', 165.

1 tablespoon = 95 calories, 8g fat, 3g carbs, 4g protein.

Good luck.

One word- coconut butter! Same as coconut manna but I get it at my local Fresco ($1.49 for 1 lb- made by Grace). I can eat a whole one of those for a 1000 extra calories.

Magnesium does miracles for headaches. http://onlinelibrary.wiley.com.proxy-ub.rug.nl/doi/10.1046/j.1526-4610.1996.3603154.x/full

Simple bro...Check out the almond banana smoothie on cakestopaleo.com or Juli's smoothies on Paleomg.com...

-Have you tried pastured heavy whipping cream? Pour it over frozen blueberries. A lot of people who are dairy intolerant can eat the super heavy cream.

-Can you not tolerate coconut milk either? Paleo Comfort Foods has an awesome gravy recipe with coconut milk (and I used bacon grease as my fat) that I could eat poured on everything (I love it on kale).

-Buy grassfed beef tallow and spoon it into any ground meat you are cooking. Also great for cooking veggies. Or leftover bacon grease from high quality bacon.

One way to up your calories is to drink fat-laden beverages, like coffee/tea with butter and coconut oil. This isn't just a tool for those on a bulletproof protocol, you can also drink them as you normally would coffee and tea. Paleo hot chocolate made with cacao powder and coconut oil is another option.

Try adding more carbs to your meals, like sweet/white potatoes and starchy vegetables. It will give you energy for your workouts as well as provide more calories.

I don't get migraines myself but personally I've found that eliminating olive oil in favour of coconut oil has correlated with me feeling far less high-strung and less prone to minor headaches. I don't know if it's due to eliminating olive oil and I don't have any scientific evidence to support it, but maybe it's something you could experiment with.