Well, you have some special needs in regards to your back, can’t help you there.
Fitday.com is a free resource to help you keep track of your intake. Includes goals, graphing etc…if your into that. Breaks it down into percentages as well.
As far as squating, I’ve learned a new one just recently that I have fell in love with.
Bulgarian split squat. Do a search on it to see what it looks like, consult your physician, try it out…whatever.
Good luck on your journey.