Levenolle is an effective emergency contraceptive when taken as early as possible. You took the pill within the recommended time period of 3 days.
The website for Levenolle does say this, "Levonelle® One Step is not 100% effective and will not prevent pregnancy in every woman.''
This pill does affect the menstrual cycle. After taking Levonelle® One Step, most women will have a normal period at the time they expect but sometimes, your period might come earlier or later than usual. It can also be lighter or heavier than usual. Or, you could have some 'spotting' until your next period. If your period is more than 5 days late, unusually light or unusually heavy you should contact your healthcare professional. Again, this is from the product's website.
It is highly unlikely that your are seeing the outline of your uterus. Muscles cover the organs in the abdomen including the uterus. It is impossible for you to see or feel your organs.
If you had a normal period in early July and have not had unprotected sex since, you are not pregnant. Remember, taking an emergency contraceptive pill will cause a period to come early and late.
I hope that I have answered your questions and calmed your fears.