Am I pregnant

I had sex January third and the week or two after that I started spotting here and there but nothing heavy only light pink when I wipe.. it’s been 6 weeks and I took 5 tests and it says I’m not pregnant and two or three weeks after I had sex the doctor took a blood and said I wasn’t. I have had my period and this app says I’m 7 days late. I am having severe stomach pains and I am using the restroom a lot and very sick. I had one baby (he is one now) but this seems different I wasn’t throwing up in the beginning like I am now. Is this a sign of pregnancy?