The first GP appointment is nothing really. They don't even confirm your pregnancy anymore. They just tell you to take vitamins etc. I didn't even see a GP this time. Just phoned up ad told them I was pregnant. Personally I would tell him not to bother and save his days off for the more important appointments such as your booking in, and scans etc. If you need extra scans or appointments your partner will need quite a lot of time off.
For me I'm 9 weeks and I've already had one midwife appointment at GP office, 3 scans, my booking in appointment and then gone back for repeat bloods. And I already know I will have extra consultant appointments and 3 extra growth scans as well as the 12, private 16 and 20 week scans. So my partner just attends the scans and important appointment, otherwise he would be off constantly! Lol.
For your booking in appointment they will ask about mental health. This will affect the care you are given if they feel it's relevant. If it's not then they won't mention it again. Here they ask for 5 minutes alone to discuss mental health and other issues like DV. Xx