Hi and welcome to HCM,thank you for your query.
Well these are not some classic signs of pregnancy
and if pregnancy test was negative then you are probably not pregnant. however you should do some tests to verify is there any gynaecoilogical disorder or hormonal
imbalance. Also this discharge may indicate std
too so do std testing. To evaluate pain in lower abdomen you should do ultrasound
for start and see is there any pathology in pelvis and around ovaries.
Wish you good health. Regards.