Why is my aquarium so foggy?

so i have my aquarium which i got 2 weeks ago, its 5 gallons and i have the filter running and everything. I have a heater, a lamp, a filter, plants, seashells and gravel, and 1 molly fish. The water is currently at 80 degrees. The water is clean but when i look through the glass it is very foggy and blurry. I cleaned to the whole aquarium numerous time and the outside glass too. PLease Help, is this something bad?