Oh poor you, what a dreadful night. I do totally sympathize, it sounds a bit like my Saturday night. Last night wasn't too bad, but he was in bed with me. Fed at 10pm, then 2am, then managed to settle him back to sleep without feeding about 5am, and he woke up at 6.30am. He's still not hungry though. And I'm still knackered.
The difference is that DH and I are not arguing about it because we're in separate rooms and haven't attempted any sleep training, so he just sympathizes with me and takes him away if I need it (but I do know all about falling out with other half about sleep though, when DS1 was a toddler). Also, I guess I am not really doing anything to tackle it. I am just accepting that for now he wants feeding in the night, albeit frequently and he doesn't necessarily need it. So I attempt to settle him without feeding depending on what he sounds like, but quickly resort to feeding if this doesn't work. I figured that while I am bfing, that's what is going to happen! But then I don't know anyone still bfing at this stage, so I don't have anyone giving me any advice. I am hoping he's going to grow out of it on his own.
Having said all that, I still weep in the middle of night sometimes! You must be completely knackered. At least if you had an evening, that would be better. DS2 sometimes wakes around 8.30pm at the moment - until 12 weeks this would have been unheard of and it does my head in.
I don't have any suggestions that you won't have already tried. Other than (brace yourself), would he go to sleep do you think if you both went to bed together at 7pm? Forget having an evening for a while, I know that's hard especially with your first DC. Forget trying to sleep train, clocks, etc, just to get some sleep? A week isn't going to make any difference to him, but it may give you enough energy to tackle it head on and do what you wanted re: the sleep consultant? Not a great suggestion I know, sorry.