I had to tell my boss around 7w because some days I was literally passed out on the couch most of the day (downstairs from my coworkers so not sure if anyone saw me) and he was very supportive, told me it was understandable and he won't tell anyone else until I was ready. We can work from home so he told me if I needed that more, he would totally support me. I know not everyone can have a supportive work place but sometimes telling your boss may work out better than you think. I also figured that if the pregnancy didn't work out, I'll also need time off from work so it might be relevant nonetheless. DH also told his boss after first scan and his boss was also supportive of him possibly needing to be there for me more at home.
Other than that, really not sure how to cope except to just sleep. I found it really hard to fight against my body, there was no way I could force myself to think clearly when I was tired, I had to just give into it. It has gotten better this week (11w) so.. hang tight!