Thanks for writing in.
I would recommend you to repeat pregnancy
test again. even then if it is negative, then you can go to doctor and get ultrasound
examination done to rule out condition called polycystic ovary disease.
Again get your thyroid
levels checked as hypothyroidism/hypothyroidism can also lead to irregular bleeding.
If you are having anovulatory cycles then also you will get irregular menses, and if you want to get pregnant then ovulation induction
can be done with the help of medicines.
So consult your physician and rule out above mentioned possibilities. I hope I have answered your query.