What Are The Symptoms Of Potential Pregnancy?

Hi, I m 21 years old I m often have unportected sex so I m always stressing if I m pregnant. I ve maybe puke a total of 10 times my entire life so I don t believe I would have morning sickness to soon. I m having short periods up to 3 to 4 days, there is heavy bleeding in my bowels, bad cramps, lack of appietite, seem to be tired alot, moody, I do have alot of gas and I ve notice constant jerking in my stomach and I m always having indejestion I ve also been faint my blood pressure seems to drop alot. I do have alot of stress going on so it s hard to tell if all this is just stress or something bigger. When I was 16 a doctor told my I have hpv. I ve taken pregnancy tests but they either come out negative or unreadable. Have any suggestions?