Is it still possible for me to be pregnant ?

Oki, I should've started my period last night. I'm usually on time, or a few days early. Me and my now ex boyfriend were having unprotected and he came inside of me 5 or 6 times. I can't remember the dates. Anyways, I took a test this morning when I woke up and it was negative, But I've been feeling like I'm going to puke for a week or two now, I've thrown up quite a few times, My hurt, and my are looking a little darker and I can see the veins... I've been going to the bathroom almost double what I use to and have been eating more... Could I still be pregnant even though the test said I'm not ?