Okay me and my boyfriend had unprotcted sex on July 19, and my period was late so I thought I was pregnant and I took a home pregancy test , & went to the doctor & took one also the results were NEGATIVE , but the next day my period came and it was very LiGHT and thin .

Is that normal ?

If the doctor said negative, then 99.9% sure you're negative (assuming a competent doctor).

Are you sure it was your period?

Did they do a blood test or just a urine test? If you had unprotected sex then it's possible that you are, of course. However, if you did 2 tests that are both negative and have had a period the likelihood of you being pregnant is pretty slim. Wait a few more weeks and if you have symptoms that are similar to those of pregnancy go to the doctor and ask for a blood test to be 100% sure. It was either too soon to tell, or you aren't.

Wait about another two weeks then take THREE clear blue tests a few days apart if ANY OF THEM are positive go back to the doctor.

It may be to early to determine pregnancy!