Am i pregnant or not? so confused can anyone help?

I will tell you the whole story because i am so confused. I had sex through out the month of may up until the 28th of may. Around the week of the 15th i started feeling nauseous and dizzy but then it passed until the week of the 22nd i got nauseous/dizzy/headaches/mood swings/backaches/dry mouth/ tiredness and also my stomach felt stuffed like there was a lot of pressure but then on the 29th for 3 days i got my period and it was light but heavier then spotting then i felt ok but a few days later i got all the symptoms back so i took a fact plus test and it came back positive, so make sure because it was light but readable inside i took 4 more tests 2 fact plus and 2 clear blue all but one other fact pluse test came back negative? i am so confused and don't know what to think please help i want to know if i am pregnant or not!!??