Please no judgment anxious mom here need advice

So I live in Michigan and am currently 30 weeks pregnant. I will be giving birth at Genesys in Grand Blanc. I am just curious about the testing of meconium and how far back THC goes. I haven't smoked in a while but I can't exactly remember the last time. I never smoked a lot just enough to feel better I have bad nausea while pregnant. I have never been told at an OB appointment that I tested positive in my urine. They did ask on my first appointment if I smoked and my stupid self told them I did before I found out but stopped immediately which was true until the nausea hit at 9 weeks. I know for sure I haven't past 24 weeks but im truly unsure of the last time I did. I have a 4yr old that I have shared custody with her father (not baby father to the newest) and worry about a potential cps case and if he can attempt to take her away from me. I have no open cases and do not have any issues but my anxiety is getting to me on this. I dont want to lose either child my babies are my world. Please be nice if not please do not comment. I am already my own worst critic and the guilt is eating at me. I hope this all makes sense.