I only got my period for 3 days then it stopped. My breast are swollen and tender,and I took 2 home pregnancy test they were both negative.Could I be pregnant and not know it

Well, you could be but it doesn't seem likely if you got your period. The breast tenderness may just be from your period. If you're still worried it can never hurt to go to the dr's and have another test there though. Hpt are good but they aren't always 100% reliable.