I had my daughter 3.5 weeks ago, my postpartum bleeding stopped completely and then Monday I started…

I had my daughter 3.5 weeks ago, my postpartum bleeding stopped completely and then Monday I started having on and off bright red bleeding with clots and cramps. The doctor said just to watch it and then today I got it even heavier than before, it soaked my pad, my shorts and was running down my legs within 20 seconds. it slowed back down after i showered. I called the doctor multiple times and they keep saying someone will call back in 20 mins but they don't call back. getting worried. help??