Just Found Out I Have Gallstones

I had an ultrasound and barium swallow xray on wednesday. They wouldn't say much, just I have to wait to see Dr. They did say I have several gallstones and on the xray he said there was nothing untoward. The dr told me it sounded like a hiatus hernia and couldn't be gallstones as I had the pain in the wrong place, he was wrong then!!
I know I need to wait to see the dr but I need to know now what I can eat. I know to cut down on fat but what is safe to eat?

Before the scans I had 3 attacks a month apart. Each time I had eaten plums(as well as other things). Does fruit cause a problem if you have gallstones, I can't find any info that mentions fruit.
When I had the attacks, I got really bad pain, with no way of easing it lying, standing, doubling up etc. It was very bad and each time lasted about an hour. It felt as if food was stuck in my abdomen. The pain started in the middle just below the breasts(where the bra meets in the middle) and gradually moved own. The last attack was after seeing the dr so I had painkillers, it didn't last as long and wasn't as bad.

I don't know how many gallstones I have or how big yet and also don't know if there is anything else wrong too. I am scared now. I know the only real thing to do is to have the gallbladder removed and it is to help me but still scared. Are there any alternative therapies or herbal treatments? If I eat healthily now will I still get attacks until I have an operation?

Thanks for listening, everyone says it is a simple op but I have never been ill before so am very scared. I know it isn't too serious as lots of people have this. Is the ultrasound enough for diagnosis or will I now need the endoscopy too?