Might be pregnant after a miscarriage

Hi the everyone not sure if I'm pregnant I had a recent miscarriage on Dec the 23 2015 and I had 2 huge blood clots come away from me which was a twin pregnancy but after I went to the hospital on the 27 Dec my hcg levals went down to nothing me and my partner had u know what on the 6th of Jan and about 4 days ago I had a huge discharge which was brownish and had abit of blood in it not enough to be a period and laitly I have felt pregnancy symptoms I know the signs as I have 5 children already but my nipples are dark and itchy and sore when I touch them and I've been feeling off color like when you are 2 much and you feel slightly sickly my bum cheeks are sore when I sit or stand and I have aches round my back and belle but all the preg tests are negative and if I go the docs now the test will still say negative my belle feels full and my uterus is sore round the sides of my belle if I was told I'm highly fertile after a miscarriage and wondered if the brown stuff was an implantation bleed or the last bit of the miscarriage if there are any gynecology consultants out there who can help that would be great also I had a jelly like mucus in my underwater the other day and I have had a mucus from then on its not stringy just white cremey and I have to ware a pad because I feel wet otherwise thanx for your help my period should be due the 23rd Jan but then again after a miscarriage I don't know when il get my period if I'm not pregnant xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx