I am trying to get pregnant since 3 mons. Every time I do a hpt, it turns out negative. My period has not started yet. My menstrual cycle varies every month(30 to 35 days). My period should start on 20th May if it is a 30 days cycle(which did not start) or it should start on 25th for a 35 day cycle. I don't have any signs of my usual PMS except getting pimples and little painful nipples for few days. But since 2 weeks I have a low back pain which is not my normal PMS. I took a hpt today morn with negative result. Since a week after my morn breakfast of oatmeal I am experiencing diarrhea like bowel movement. Is it an early sign of pregnancy? Could I be pregnant?

There is no way for us to tell you if you are or are not pregnant. Try waiting until after the 25th to take a pregnancy test. If it is still negative, wait another week and test again.

Thanks for replying.
Why does my menstrual cycle keep varying from mon to mon?Is it normal?Does it make any difference in my efforts to get pregnant?

Well you unfortunately you need to wait! I know how hard that could be,,
Well varying periods decrease the chances of conceiving because you can't predict the dates of ovulation, so I suggest using those kits to detects when your ovulating, Good luck :)

Yeah fortunately we've these OPKs. I've been using them since 2 mons. This waiting period is killing me. After all this wait when the test comes back negative, it is a big disappointment.

I know! I'm really sorry about that! But all you can do now is Wait,
But in general you should try and relax specially when trying to conceive, don't stress so much about it ~i know how hard that could be~ but it effects your chances of getting pregnant,