moms. is this normal at 16 weeks?

I've felt amazing for the past couple weeks but today I feel like CRAP. My boobs are so sore and tender today, I'm nauseous a crazy amount and even took nausea meds. And I keep feeling like I have to go to the bathroom (I'm really constipated) and tmi?? It's been at least 9 days since I've gone, but this is nothing new. It's been anywhere from 9-12 days apart each stool since I've got pregnant. When I try to go to the bathroom when I have the urge I get an overbearing urge to puke. I feel like I can't even get up and make myself food today but I have blood sugar problems and have to. Also, my stool keeps having tissue like mucus on it for the past couple months. I just feel like everything's hitting at once and I'm not sure if symptoms are on and off for other mommies or not, but I'm feeling really down in the dirt.