Thanks for your query,
It seems you are having some sort of viral infection. It is not associated with pregnancy
.In TVS after 5 weeks , heart beat should be visible along with embryo. If it is absent then , it is not normal. It has to be reconfirmed after 1 week by USG before giving final diagnosis. You need to undergo various investigations to pin point the cause so that it can be treated.
Best of luck and take care..
Hope it helps..