Samsung Galaxy S5 E-mail Issue

I recently set up my e-mail feature on my Galaxy S5. However, after receiving and reading a few emails, I deleted them all. A message came on screen saying that I have no emails in my inbox. Looking at it on the home screen my email icon still has a notification for "1" email, and the inbox folder has a "(1)." There are no emails left and I have even tried loading more emails, and still none have arrived. Any ideas?

Look at the "combined inbox".
It's found after you click on the 3 bars on the top left in email.