Post partum bleeding

How long do the cramps usually last? Also is it normal for the bleeding to pour out after standing up? I get some clots nothing bigger then a fun size candy. It's been awhile since I went through this so I can't really remember. I didn't have cramping yesterday but I did do alot yesterday I went to the grocery store and a few appointments and I did lift more then I should unfortunately. I had my baby 7 days ago also. Today I've had alot of back pain and some uterine cramping with more bleeding then yesterday.