Why do you think you have a Candida even though you were not diagnosed with it? There is always the possibility that you don’t have a Candida but some other digestive imbalance that makes you feel so unwell. Especially since you find it hard to digest vegetables while you are ok digesting a burger? Maybe you can’t handle fiber that well for example. Raw vegetables and salads can be hard to digest especially for people with leaky gut, so try steamed or sauted or making pureed soups. Then again juicing works well too as Raster said. But in general it sounds to me that you’d be better of eating foods that you know and can feel that are easy to digest and better for your system. It could be also that you need to build up your tolerance of veggies over time especially if you did not eat much of that stuff before.
What could be contributing to you feeling so poorly could be forcing yourself to eat stuff that you are not able to digest and that therefore leaves you malnutiritioned as you are not absorbing the nutrients. That’s why it’s good to find information in forums like this but in the end of the day you will need to discover for yourself what works and does not work for you.