Hi congrats on your pg...
I fell pg with our second when the first was 8 months, at the time I was scared but the idea of two so young does grow on you.
My sister is 7 months pg and like you in the begining she didnt really know if she wanted another ( her 4th ) but as time has gone on she has come to terms with it and is now verry happy about the prospect of having another bub around.
So hang in there and let your partner know and enjoy this special time together.