What Causes Delayed Period While HPT Is Negative?

well i had sex with my boyfriend in december with no problem, the only problem was that i had some white liquid coming out of my vagina but i thought it was normal...in january i had my period n in feb till now i havent had my period yet n all tests i have had are all negative (all this time the white liquid still comes out) recently i feel bloated n the white liquid seem to be solidified now but not completely solid anyway and i was just wondering whats wrong with me...if you could help...thanks