@conniechoi84 Welcome to Mayo Connect. Thank you for joining us and for your great questions. My blog has my entire journey up until I develop PTSD. My blog is still active. I'm so so sorry that your mother in law has lung cancer. It's terrible disconcerting when you are hit in the head with having cancer. She must have had an Xray. CT scans will bring her closer to a diagnosis. There will be lots of blood work and maybe breathing tests.
Your mother-in-law is very lucky to have the both of you to support her. This is what she will need from now on, if it indeed is cancer.
Don't let her be indolent. Eating, a balanced diet and exercise are the most important things for her right now. She probably isn't getting a good night's sleep but if she can nap encourage her to.
I also suggest that you concentrate on one thing at a time. No what ifs! They will drive you batty. There are no answers to what ifs. The most important psychological thing for your mother is for her to feel in charge. She has just had her world kicked out from under her. She needs to get as much control back as possible. She needs to make all decisions after discussions with you and her doctors. Right now honesty is most important. That days of hiding things from people are long gone, buried deep in history where they belong.
You will be learning an entire new world and vocabulary. Make sure that you line up your priorities, one test, one day at a time. And take care of yourselves as well. If it is cancer than you have a long ride ahead of you.
Please let me know what the results of the CT scan are. And what kind of cancer they think that she might have.

Here is my entire blog so far. I am still writing. https://my20yearscancer.com/ I hope that you pass this on to your mother in law to read.