Pregnant with no3

I’ve just found out I’m pregnant with baby number 3. I have two little boys, 2 and 1 and had severe HG with them both. It was definitely worse with my second, I couldn’t tell you the number of hospitalisations I had with him. I am absolutely terrified right now. I have no idea what to do! I thought we’d done everything we could to prevent this, but we clearly didn’t do enough. I haven’t told my husband yet because he isn’t going to be happy, which I completely understand, but I’m not sure I can handle his emotions too right now (I will tell him just not right now whilst I’m so emotional). Has anyone else been in this situation? Any words of advise??