pulling sensation from belly button

Hi all,
I had my last period on 24th of last month. I have been trying to conceive. From last 2 weeks I have this strange feeling of something pulling from my belly button to the left of my abdomen. I am also having a bloated tummy from past 1 week. This bloated feeling is so inconvenient and tight that it is causing pain in the sides of my back. I feel like sitting with a pillow behind my back. I asked my mom about the discomfort in left side of abdomen and she told me its usually caused because of sex. I was not able to sleep since last three days and went and checked with a doctor yesterday. He suggested an ultra sound scan. I am expecting my periods on 23rd this month. Today morning I took a home pregnancy test with velocit test kit and it turned out negative. Is all this bloating and gas and pulling sensation from belly button caused due to pregnancy or is it some other illness. I am damn scared because I have read of hernia on the internet and damn scared about whether this is some kind of hernia or kidney problem. Please advice what to do. I am feeling very uncomfortable with these symptoms. Also I would like to know when is the exact time to do a pregnancy test. Should I check only after I miss my periods or can I do it before also.

Thanks and Regards,
Anu

 

Dear luckwaves,
Thank you so much for the information. Based on what you said about the test I think iam not pregnant . Will wait for my periods and see the next cycle. Thanks once again.

Cheers,
Anu