I might be pregnant with a iud?!

So for about a week I haven’t been feeling like myself. I’m gaining weight, peeing very frequently, my appetite has gone up. Today Is the day I’m suppose so start my period but still nothing. I took a pregnancy test but came back negative (I also think it was to earlier anyways). I currently have a paragard iud (I had it for about a year & half) and I’m a mother of two boys already. Have anybody ever got pregnant with iud? What should I do?