Need a committee to plan the party!

I have not organised any function on my own in my 'new' house. I have been telling my family there will be a house warming, but we had none. It has been 4 years since we moved in, and the house is hmmm very warm already as it is. There were no major function held in my house and many of my friends relatives been asking me when are we gonna invite them to my (then) new house. So  I have decided to do something about this situation.

First of all, I have NEVER organised any function, I mean real major one. Daaniya's and Imaad's 40th function were held at their grandparents' house. I had very little to do with that, just buat-buat sibuk here and there. Overall, it was a successfull functions,

Now that I am organizing Daaniya's birthday and Imaad's Aqiqah, I am panicking BIG TIME.
It's just SOOOO many thing to do. And so much money flowing steadily out of my pocket.
I am just too worried, it will turn out in a disaster, I keep on thinking the worse, no turnouts, not enough food, heavy rain or caterer screwing up. Damn I need to calm down.

I really hope everything will go on well,  this is first actual birthday party for Daaniya, since the twins and Mohd all born within same week, it is a birthday party for 4 of them, and also adding in my nephew 13th birthday which falls on same date as the twins. So there going be lots of candles to be blown that day.