It could also be introducing a new routine such as diet and exercise can cause your body and hormones to get out of sync. Im a medic in the Army and females come to the TMC all the time from basic training and,AIT with the same issue. Take another test and if its negative than see your doctor. It could be something more serious but chances are it is just as simple as your new routine.
I don't really think that u are pregnant but the pull out method is never full proof! My husband and I are pregnant with are 3rd and we used the pull out method and still we got pregnant! A man can pre ejaculate and that can still result in pregnancy! So if you don't want an unexpected pregnancy I would advise using a condom or get on birth control, because u are definately playing with fire when using no protection and the end result will be a sexually transmitted disease or pregancy! Good luck hon!
WELL...... My husband and I did the "pull out" method. he did not ejaculate inside me and I got pregnant with fraternal twins! Which means that I happened to drop two eggs and they both got fertilized. So the pull out method DOES NOT work! I always heard that it's not guaranteed but I had no idea that that could have produced twins! Seriously, it was like three strokes and he pulled out! I'm due in Dec. so be careful. And yes, take another test, because of your bleeding it doesn't sound like it but grab one from the dollar tree (they do work) and then you'll know :)
Take another preg test just for thought. I don't believe you are pregnant....I think it might just be irreg period....Dr may put you on birth control to regulate it. Call your Dr.
If your partner did not ejaculate during sex, the chances of becoming pregnant are limited even further. The regular chances of becoming pregnant can be imagined as a bunch of people blindfolded, in a football stadium. The "egg" can be represented by a basketball at the 50yd line. Only one of the blindfolded people would need to find that "egg" but it is less than a 50/50 chance for you. There is still a slight possibility so I would advise taking another pregnancy test. However, weight loss and pregnancy are not related too well. There may also be other reasons why you are having an irregular period. Your best bet is to either see a healthcare professional or take another pregnancy test. I hope this all works out for you and good luck!