I think im pregnant bro...

Im not even sure where to begin with this...First, I have irregular periods, and cant remember exactly when my last period was, but im almost sure I shouldve already got it again. I began with this cramping, some what like menstrual cramping, but it didnt exactly feel the same. Ive noticed an increase in my appetite. And my jeans are really tight in the waist all of a sudden, some jeans I cant even button. Ive noticed pains in my lower back, one was a very sharp intense pain and lasted only a second. Then the pains turned into more of a dull achy pain. From what I hear, your breast get swollen, or tender. Mine dont feel sore at all, my nipples were a sore a few days ago, but not anymore. I havent actually vomitted, Ive felt naseous, and dry heaved, but no actual vomit. My mood has been unpredictable here lately, I'll get extremely pissed off over little things, then just as fast as I got pissed off, I'll be happy again. And get kind of sad out of the blue. But mostly its back and forth of me being mad and happy. My discharge has increased also, and I feel constipated. Im sorry im practicly writing a novel here, I just need to get another opinion on this. Im 16, turn 17 in December. Im still in High School. I have a job. My boyfriend also has a job. The only thing that is really worrying me right now is, im in foster care. Ive been in foster care for about 4-5 months now. My foster parents love me, this was only going to be temporary but they asked if I wanted to stay until I graduate and I agreed. My mom said awhile back, if any of her foster girls got pregnant she would keep us, she would just "wring our necks". But from my 'symptoms', do I sound pregnant? Please take your time to read this and respond, I atleast need one other opinion, I would really appreciate it.