by the way im 25 y.o

I took a home test (twice) around august and both came out negitive and then later in October I took another urine test at the doctors which also came out negitive..
I haven't really been stressed out over it, or thought about it too much until recently, but after reading this I began to wonder about it....is there a possibility that I may be pregnant? -- After reading up on the symptoms I went through and thought about it. The last few months I've been feeling ill (sick to my tummy) and my breats have seemed slightly fuller and sore. And until now I tried to have a home test but still negative. Any advice and ideas bout this? please help..
Any thoughts ya'll might have would be nice to hear! Thanks.