Pain when eating!!!
While avacados are soft feeling they are still very dense and sticky so even mashed up they are thick and very fibrous so it was probably just more than your new tummy could handle. Probably not good for eating until later on. Try something a bit easier to get down like cottage cheese or some pureed chunky soup. Your tummy will tell you right away if it doesn't like what you are giving it. Always listen to it!! Try some softer easier to get down foods and wait awhile before trying many veggies they are harder to digest unless cooked to death. Don't be afraid just go back a step in your eating plan before trying anything like that again. Good luck!