Pregnancy or Birth Control?

Patient: Is it possible I’m pregnant or just all my birth control?

Symptoms: I am an 18-year-old female with an almost three-year-old son via c-section. I have the birth control implanon in my arm that has about six months left. I have been experiencing very new symptoms.
I have been bleeding since July 7 and my fiance and I had unprotected intercourse July 2. At first it was dark brown spotting for about a week then it changed to bright red and the flow was a little heavier, but the consistency wasn’t like it normally is for my periods; it was just like water. I have been experiencing SEVERE nausea, I can hardly find anything to eat that won’t make me feel like I’m going to puke my stomach out and I can smell from a much further distance than I was able to especially for things that make my nausea worse (cheese and barbecue sauce, which used to be favorite foods). I have been very tired and my mother suggested iron deficiency from all the bleeding, so I took iron supplements that made no difference. I have had bloating, constipation, moderate cramping, and SEVERE lower right side back pain that comes and goes. My emotions have been extremely heightened. For example, I asked my fiance if he was coming to bed with me since I had work early in the morning and he said he wasn’t tired; I began to cry. I have been stumbling and falling more than usual since this started. I have also had an increased need to urinate without any changes in fluid intake and my breasts and now swollen and mildly tender to touch. (P.S. I’m overweight)