Oh I'm so sorry you are having a rough time at the moment. But you do need to start considering the baby. So have you tried enlisting the help of a friend? Do any of your close friends know what you are going through. Sometimes if you can delay the purge by talking to someone, a 'buddy', then you can sit back
and realise that you don't NEED to purge.
Also how about having some other distractions to hand like a book of the developing stages of your baby so you can look up what is happening to it right now. Or a name guide for thinking of good possible names.
My main advice though would be to tell your doctor and/or health visitor imediately. For your sake as well as the babys. You need help to deal with not just the physical symptoms of the bulimia but also the mental anguish you are suffering. It sounds like a hell of a lot of stress is going on right now which is such bad timing for you considering your condition!
So please don't go through all this alone, get help
and come here whenever you need a friend to talk to who won't judge you for your bulimia.
All the luck in the world from H xoxoxo