Spotting twice in a month, on cd43, 3 bfn, don't know how many dpo coz of the 2 spottings

Hello everyone,

I'm just so confused about all this spotting business. My last period was on 03/15/2014.

We made love on the 03/24/2014. I spotted on 03/27/2014 red and only when I wiped for 2 days. I spotted again on 04/05/2014 Red and only when I wiped. I tested on 05/19/2014, 05/23/1014 and 05/27/2014 and had bfn's. My jeans are very tight and have started rolling down my waist and my breasts seem a little bigger. Don't know if this is because I'm just gaining weight. I had bad back pain, bad cramps, hot flushes some evenings and a fever of 101 on 05/05/2014. I'm 27 years old. 

Plz advice whether this may be pregnancy, weight gain r period problems. Should I see a doctor r should I just leave this as a weird cycle? Were the spottings ovulation spottings? I spot once every month.