Well done! You've had a rough time al lright!
After three I've learnt to take a doctor-like approach- working through (with the doctor too) eliminating the possible reasons, and on the way we've very often/ nearly always found the reason behind symptoms or behaviours. A good reference book helps so much as you then know which things to ask to be checked and can work as a team with the doctor. I personally found Robin Barker's 'Baby Love' book a great source of info, intelligently written and stating clearly what many, some and few babies do, which helps give you some perspective when it's your first. Good luck!