1st time mum

Terri • I have one little girl who is 2 years old
I am 4 weeks and 1 day pregnant with my 1st baby. I got my BFP yesterday! I haven't told anyone yet as I am getting married on May 6th so I want to tell my partner on the morning of our wedding so our videographer can film it. Not planned it yet but if you have any ideas feel free to tell me below! I won't be seeing him the morning of the wedding so will need to be a gift or film. Anyways.......
What are the 1st things I should be doing? I have been taking folic acid, omega 3 and magnesium for sometime now. When should I ring my Dr? What pregnancy essentials should I invest in? What where your must haves? 
I suffer with bipolar so I rang NHS direct and they said my meds where ok till I get to see my dr.
Anyone else a mental health sufferer? How did you cope? I like the thought of getting my own head round the pregnancy before the crazy starts so I have 6 weeks :)
Thank you in advance xxx