When I was first pregnant, the pregnancy test didn't come back positive until I was a week late, so it's possible that you really are pregnant, even if the test was negative. But unless the test was "broken" (perhaps out of date, or something), then you won't be several months pregnant, because the amount of hCG in your urine (what the pregnancy tests test for) remains high throughout pregnancy, and if you were 2-3 months along, you'd be sure to have a positive pregnancy test.
It's possible your uterus is sensitive enough to feel fetal movement early, but the typical 1st-time mom feels fetal movement around 18-20 weeks, and 2nd-time moms feel it a few weeks earlier. Fetuses don't begin to move until several weeks along, so it's extremely unlikely that you felt actual fetal movement. I've had sensations like you describe several times when I wasn't pregnant -- I had regular, normal periods all throughout -- and it felt ***exactly*** like early fetal movement. But it must have been gas, because I know for certain that I was not pregnant, and definitely not 2-3 months along!