Suspected Bruises

Has any one woken up before with bruises on their legs\arms with no apparent reason or recent injury?
This condition has been happening to me ever since i was a child. I wake up and suddenly find red or blue bruises on my legs or arms. They don't have to hurt sometimes though. I consulted many doctors about this matter and still do, but you know the typical answer you get here; it's normal.

It got me to the point where i believed that demons beat me at night since the condition is magically unexplained 'don't ask why LOL'

So i googled it, and those seem to be the medical explanation for it:

• effects of medications or supplements — aspirin, anticoagulants (blood thinners), corticosteroids, and dietary supplements, such as fish oil, ginkgo, ginger, and garlic.
• a bleeding or clotting disorder.
• nutritional deficiencies of vitamins B12, C, K, or folic acid.
• inflammation of a blood vessel(s).
• liver disease.
• sepsis — a widespread presence of infection-causing organisms or their toxins in the blood or tissues.
• chronic inflammatory diseases, e.g., lupus.
• certain cancers, including Hodgkin's disease, leukemia, or multiple myeloma.

[Source]

The reason why i highlighted Liver Disease is because it's a genetic disease in my family. And though I've taken a vaccine against it, I'm beginning to be paranoid. Should i be worried?