Menstruation cycle is this normal?

[Vivian M]

I am 23 and have a 28 day menstruation cycle which lasts for 5 days. Recently as in from last month i have been experiencing 1st and 2nd day having a normal to heavy flow, which i have been passing some blood clots on both days. On the 3rd day the flow has slowed down, to having no flow at all. Then it picks up again on the 4th-5th but barley flows. This is strange to me because i have never experienced such a cycle before. Please help. Thanks in advance