All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
As long as the blooding is constantly coming out in the manner that you mentioned, then you are in a state of Istihaadhah (bleeding outside your monthly menses). A woman who is in a state of Istihaadhah is not prevented from praying and fasting. Rather, she fasts and prays with the exception of the days of her regular monthly menses, as the Prophet told Habeebah when she was in menses: “Keep away (from prayer) as long as your normal period used to prevent you (from praying), and afterwards you should perform Ghusl (and pray).” [Muslim]
What we understood from your statement “I am not sure about my period dates”, is that you do not remember now whether your monthly period was at the beginning, middle, or end of the month. If this is what you meant, then a woman who is in a state of Istihaadhah who forgot the exact time-period of her monthly menses in the month, but she remembers the number of days of her menses, then she does not pray for the length of the time-period of her menses from the beginning of the month, and then she should perform Ghusl, fast and pray.
Al-Bahooti from the Hanbali School of jurisprudence, said in Kash-Shaaf al-Qinaa’:
“If she knows the number of its days; i.e., the days of her menses, but she forgot the time of its occurrence, like if she does not know whether she has menses at the beginning of the month, at the middle of the month, or at the end of the month, then she should refrain from praying during the same number of days (of her menses) at the beginning of each lunar month.”
If you also do not remember the number of days and you do not remember the time of the occurrence of your menstruation in the month, then you avoid praying most of the menstrual period, six or seven days, from the beginning of each (lunar) month.
Al-Bahooti also said in Kash-Shaaf al-Qinaa’:
“The same thing applies to the woman who forgot the number of days during which she has menses, and the time of the occurrence of her menstruation, then she should refrain from praying [and fasting] during the time-period of the usual duration of most women's menstrual periods, at the beginning of each lunar month.”
Allah knows best.