Thanks for consulting us.
This condition is called pregnancy
of unknown origin (PUO). All the advice your doctor gave you is appropriate & you should be careful about the pain & should have a repeat TVS next Friday.
This could be an ectopic pregnancy, a very early pregnancy or a missed miscarriage
One more very informative test is to repeat your beta hCG
test after 48 hours of the first test. This will give very important clues about the probable diagnosis. Serum progesterone
levels are also very helpful, So better to go for this test too.
Wish you good health.