Hi guys need advice ....

I had my depo injection around 3 weeks ago now and have recently been having weird symptoms.

I gave birth to my first child in September and feel exactly like i did when i fell pregnant with her.

Having really bad cramps and my belly feels harder than usual, making exsessive trips to the loo and my appetite is substaintailly different ?

I have taken a pregnancy test and it has came back negative, but i still feel pregant.. Can anyone spread some light on this for me please ???