Could I be ?

On December 13,2018 I had my cycle and then on the same month I started spotting on the 24, 25, 26 only lasted 3 days. So now on this month on January 6-9 I was just spotting I only needed to use 1 pad for the entire day. Then again on the 20, 21, 22 I started spotting again but only when I wipe myself I did discharge brown also. I took already 3 pregnancy test and it all came out negative. At night I feel nausea and tingly and pain on my breast. I just found out it might be signs of twins but idk can someone please help me ? By the way I am a twin also.