I was married, living and working overseas, working towards ttc either then husband.
Hindsight being a perfect science I would with the knowledge I have now (there was no indication at that time how things would pan out with ex) say
Leave him certainly don't get pregnant with him
Learn a European language so you can stay living and working over there without him
Travel more, you love it and get so much out of it
Stop allowing drs to fob you off on the gynae stuff
Stop eating crap! You're getting away with it now but you won't as you get older, maintain the exercise also you'll be glad you did.
I would advise anyone your age not to tie yourself down to a relationship unless it's really awesome, no settling you have ages to do that stuff. Travel as much as possible, take chances - with travel, work, potential new friends, experiences...
Take care of your health, it seems unnecessary now as you're likely feeling pretty fit and healthy but it's as we age that bad habits creep up and scupper us! And that's everything from diet and exercise to skincare, alcohol and smoking etc it's far easier to address these issues and make healthier habits when you're younger.