My period is pretty regular. It comes every month on either the 29th or 30th. Last month it did not come. Could I be pregant? Altho test show negative

Many reasons. There are many reasons you can skip a period. Are you using birth control? What type? Are you training heavily for athletic events? Are you eating properly? When and what type of pregnancy test did you take? If you skip another period you should see your doctor. And always treat yourmbodymasmifmyoumare pregnant regarding drugs, alcohol and cigarettes..
Possibly. Though modern pregnancy tests are very accurate. It sounds like you skipped a period.