Congrats!
Everyone is so different when it comes to announcing! My OH wanted to wait until 12 weeks, but I was starting to show and was always sick and tired so I reasoned with him that if feel better if some people knew so they didn't just think I was skipping social events because I was lazy. He agreed and we told people a few days ago! I think there is a compromise of both of you are willing.
As for the pregnancy pains- they suck! I only have hip pain and occasionally I'll get heart burn, but the hip pain makes it very difficult to sleep at night. I suggest sleeping with a pillow between your knees of you bend the to p knee and extend the bottom knee, you can take a little bit of pressure off your hish and it helps a bit.
At this point with a first pregnancy, your uterus is still tucked away under your pubic bone, or just peaking up a bit. Plus size or not, it will take a while to show, so all of that is normal!