Hi Lilly. Everyone feels like crap the first few days, unless you prepared yourself by cutting back on that stuff ahead of time. Any change in diet can cause bowel problems, so have patience. Drink lots of water and take psyllium as a supplement.
About the headaches... many people go ahead and drink a cup or two of coffee per day, in spite of what the book said. That's the only "cheat" you'll ever see me recommend.
If you do give up caffeine, do so slowly over a week or two.
As for meal ideas, check the kitchen forums. There are a couple of "sticky" posts there that will link you to induction-friendly recipes.
If you're not a big cheese eater, good.
It's easy to go overboard on cheese. As for meat, you don't need a lot. Have some at lunch and dinner, and have some extra fat if you're hungry. Put a little extra dressing or butter on your veggies, or have an extra egg or two. Once you're off induction, it'll be even easier because you can have nuts, yogurt, protein shakes, and other non-meat protein foods.
Good luck!