Hi everyone! Hope you guys in the pink of health!

 

My gf had an irregular period that usually came once in 2 - 3 months. she gotten her period on the 21 december 2012. I did an oral sex and ejaculate before having real unprotected intercourse with my gf on the 7th January 2013 (pull out method).  On the 21st January, she had her heavy period that last normally. We had tried out almost 7 - 8 pregnancy test, both digital and normal and turned out negative ( first urine in the morning) . The last one we did is 3 months after sex, which was negative. By right my gf would be around 8 months right now. And she is still having her period all months, and her belly was just normal (she's quite fat). And she told me yesterday that she did a pregnancy test again last month and turned out to be negative again. Besides that, she doesnt experience any pregnancy symptom.

 

Based on the case above, is there by any chance my gf is pregnant? Might probably my gf is paranoid. tq for your answers!