Help!

Around the middle/end of January, I've had some pregnancy symptoms. But they come and go? I took several tests and they all came back negative but im still not having a normal period. Instead of my normal 5-6 day periods, i bleed for a day or two with no clotting and then it goes away?? This has happened twice now. The past couple days, ive felt nauseous again, and my hands have swollen so much to the point i can't wear my ring and my clothes are starting to get way too tight.