Should I listen to them?

about a couple weeks ago I started feeling really sick in the mornings and sometimes through out the day...but mostly in the morning like I can't step out of bed with out wanting to throw up....it feels like I have pressure on my stomach when I stand..all my clothes that I just bought a month ago are getting to tight all I can wear is tights and bugs shirts bc if I don't people ask when I'm due...but I was talking to my fiances cousins who both have new born babies and they said that my symptoms sound like I'm pregnant and that I need to wait until I'm supposed yo start and if I don't then I need to get a pregnancy test done by the hospital or go buy one...and I'm just thinking I've had many negatives and some positives throughout this relationship I'm in and I don't want to het let down again....i babysit two babies everyday while there mom's work and I love the connection I feel with them...and there's nothing I would love more than finding out that im pregnant around christmas...so ladies I need advice