Possibly Pregnant & 17; advice needed.

I'm 17y.o and last week on Thursday evening I could barely sleep due to excrutiating pains in my right side, so I took a few ibuprofen. My partner and I figured I just pulled my back out then after a few days we thought it may have be from lack of bra support. I already have fairly large breasts & have had fairly large beasts since I was 14, at least for someone my size. However, since the pain in my back grew more persistent & more intense it's almost more of a tired cramping feeling that will alter sides and go into my lower abdomen, mainly at night. I first thought I may have a kidney infection because I heard that's highly common when previously having UTI's (had one in May). Throughout the past week I find myself to have no energy & always wanting to sleep but being completely awake at the wee hours of the morning, feeling full after eating only half of a grilled cheese sandwhich and then getting very hungry in about 20minutes. (high unnormal) The sides of my breasts have become very sore which I thought could be pms until I realized my nipples were the most sensitive to where I would want to cry and they were constantly erect. I've also been experiencing a metallic taste in my mouth with the extreme urge to always be drinking water, I wake up feeling very dehydrate & thirsty all day long. I looked up what the reason for a metallic taste could be and all I came across was pregnancy or from medications that are being ingested but I've only consumed ibuprofen & have never experienced that reaction before. I found last night that my abdomen is getting more firm & tight, not due to weight loss because I actually look a little larger in that area. I've been getting nasueas but it comes and goes, my period is suppose to come between the 30th and the 1st & is very regular. Is it to soon to suspect pregnancy? I took a test a few days ago and it came up negative. I refuse to work ovulation by numbers because in 2006 I got pregnant (same menstrual cycle) in the beginning of the month when doing all the number work it's more likely to get pregnant around the 17th. I was 15, and the pregnancy was terminated at 6 weeks. The only difference in symptoms is this time i have no headaches and more pains in my back/sides.

If I am pregnant, I'm not sure how to express that to my mother again. Mainly because I don't think I could go through the emotional baggage an abortion brought on me the first time. Yes, I should have been careful & was planning on making an appointment to get back on the pill. My partner is 21 and has made it clear before we even started dating that he does not want children...Do you think I have enough symptoms to determine I'm pregnant? And how should I handle telling my mother and partner if I am? Any input on what to do if I do get a BFP?