If so, it probably won't feel like a normal period. You are likely to have stronger tummy cramps and much heavier bleeding. If you have dark or watery bleeding, and sharp pains in your lower tummy, especially on one side, call a doctor straight away.You could have an ectopic pregnancy, which will need swift treatment.f so, it probably won't feel like a normal period. You are likely to have stronger tummy cramps and much heavier bleeding. If you have dark or watery bleeding, and sharp pains in your lower tummy, especially on one side, call a doctor straight away.