Pregnancy Symptoms....?

I usually have my period the 6-10th of every month until last month i had mine on the 19th and it was lighter then usual. Since then i have had backaches, side pains, frequent peeing, nausea, mood swings, my boyfriend said my stomach is harder and starting to pooch (he has a kid with previous gf), i use to love pickles and now the smell makes me sick, i always want ice cream, etc. But i started bleeding again the 19th of this month. it is very light compared to my usual periods. I took a first responce preg test and it said negative but im to afraid to take another. I really want to be pregnant.. Since the test said negative what else could this be signs of...?