Thanks for posting your query.
It would be ideal for you to do a home pregnancy
test now. It will test us if you are pregnant or not though you had a light period from July 13 to 17.
Depending on the test report, you can proceed with the ultrasound
scan of the pelvis.
The symptoms that you are facing now can be seen in a non-pregnant state also. These are not confirmatory of Pregnancy.
Hope this helps. Take care.