You do got this! I understand. Life gets hard and we fall down. But you're getting back up, dusting yourself off, and putting the pieces back together. Good for you! ?
As for the API liquid test kit, they're not strips. It comes with little vials and several chemicals that you use (per instructions included) to actually test the water yourself. It works out much cheaper than the strips, and is supposedly more accurate if done correctly. In my own personal experience, the tetra test strips are usually pretty accurate. I used both for awhile and never had different results. For me, the difference is simply the price so I would recommend the API master test kit once you're able to get it.
As for the tank itself, you're doing what I would do (but I'm pretty new to the hobby still). Just keep watching those parameters and doing what you need to do. Once you get your tank back in order and develop a routine maintenance schedule, you and your fish will have some breathing room to actually enjoy life again!
I wish you the best of luck, not just with your tank, but also with your daily struggles. Keep your head high! Know you're AMAZING! ??
