I am looking at linear binomial regression.

I have a study that has a yes or no output so binomial. Out of 50 cases I get a yes rate of 49 so a probability of success (p) value of 98%. I want to work out the 95% confidence of this probability of success. My tutor has stated that I should use the standard error of a proportion:

Using this formula gives me a standard error rate of 0.019799

I believe I then add the p value to the standard error rate to work out the confidence interval which in this case = 96-100%

However is that at a 95% confidence interval, I read that doing the above calculation give 68% CI and I need to multiple the SE by 1.96. However it doing so the confidence intervals would be higher than 100% which is impossible?

Any help would be most appreciated.