hey... over the last few weeks ive suffered.... severe back pain .(for years, but worst lately).. glandular fever .... nausia.... weakness... tired all the time....mood swings... & now very frequet urinating....(with no pain)... bad constopation! my last period wa sthe 15th nov, & am not on any constrseptive, as i have non cancerious breast tumors..... i did a pregnancy test 8 weeeks ago.... it was posittive but faint! so i did another 2 over a week... all light, but posiive... blood tests come back negative?!!!!! im 26 any ideas?? of what may be wrong with me?