Feeling different

Ok so I have been ttc for 3 months now.. My periods are pretty predictable but this month I started having mild cramping a week before my period it comes and goes and only lasts a few minutes.. Now the day my period es supposed to start I spotted once and that's it.. Still the mild cramping which usually it's pretty severe when my period starts.. I took a PT 2 days before my period was due and it was negative.. I have no heartburn, no nausea, only swollen tender breast that started around the time of the mild cramping.. Could I be pregnant even though it said neg or am I just going crazy..