Surgery booked and nervous

I had a band put in about 6 years ago and initially lost 40kilos but I started having problems within the first 6 months and since then have had to have Fluid removed every 6-8 weeks and then refilled after a month ever since and have gained over 20 kilos I am now booked in for a gastric bypass on the 7th October 2014 in Brisbane and I am very nervous and would love to hear from anyother Aussies who have had this procedure done and how the surgery went, how they are doing now. I also have read that you can gain weight ever after having this surgery???? Has anyone had encountered this.