Hi OP!
First of all, congratulations!
Secondly, I would like to reassure you that you are most certainly not a head case and your feelings are totally normal!!
I found out that I was pregnant last October and DP and I decided not to tell a soul until 12 weeks. Unfortunately, it wasn't meant to be and I had a mc in November. The first thing I wanted to do was tell my Mum and sister and so, they were really confused and found it hard to console me when I told them what had happened.
We found out I was pregnant again in January and we decided we would each tell our families because, we realised after the first time how much we needed the support when things didn't go to plan. Of course, I am telling you this to reassure you that, you don't have to keep this entirely to yourselves at this stage, I really don't want to spook you with what happened to us. I am now almost 37 weeks and baby is very healthy!
I would recommend speaking to DH and ask him if you can each choose one person to tell now. That is an agreement that me and DP came up with initially as, it is such a relief to have someone to confide in and to help you keep your secret. I would recommend you choose someone who has already had a baby, if that's a choice as, not being able to ask questions or for advice was something I struggled with, personally! Your mum would probably be a good choice, judging by what you have said about how close your family are! - I know you say you have already told a friend and so, that may be the one person you tell your DH about or, you could take the opportunity to tell another person!
As for occasions that involve drinking - The usual fibs people tell e.g. 'I'm on antibiotics' just never work. I think the best way through it is to claim you are hungover and/or make it seem like you are drinking. Call the venue before hand or, find an opportunity to take a staff member to one side and ask them to help you conceal your secret.
Workwise - I know how you feel. I sat in many a meeting discussing the future of the company and my involvement thinking 'Oh gosh, they're going to kill me' Don't worry. No one is ever anything but, happy and the world goes on without you. There was a time I thought I was indispensable and my absence would seriously hinder the company, since then I have announced my pregnancy and retrained other members off staff. I don't even think anyone will notice if I am here now
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Most importantly, relax and enjoy your pregnancy. It is the best feeling in the world and in my opinion it has gone waayyy to fast for me!
Good luck
