Red triangle of Death car with exclamation 2003

I have a 2003 well cared for prius with 175k miles. I was driving to work the other day. I was going maybe 25-30 and bumped the curb with the front passenger tire. Then soon after noted the red triangle on the dash an a red car with an exclamation point on the monitor. I kept driving and no issues drive the same as the day before! Again drove today to work and it was fine.

Back story is I already had the check engine light on for a year. Per my mechanic and my code reader it’s the o2 sensor. He said it would cost more to replace it than the cars worth and only affects mileage. I literally only use it to drive 4 miles to work maybe 2x a week when I am too lazy to ride my bike. I got an oil change around 6 mo ago and have only driven maybe 300miles since then.

I whipped out my code reader and only codes were the p0037 code for the O2 sensor. Checked my gas cap and the tires. Everything looked fine. My parents are coming to visit in a month and I was planning to show them the sights in my Prius with possibly some heavy driving (500-600miles). They are already not fond of relying in my old Prius!! But I love her and don’t have the funds for a rental.

I went into a Google frenzy and saw some people talking about the 12v battery, oil filter, and worse the big Prius battery itself. Now I am nervous it’s an early sign for the big battery to go.

Only noticeable change over the last 1-2 years has been a rougher than I remember transition between electric and gas motors but nothing super significant. And also maybe a delayed shut off of the gas motor while stopped which has happened over last year especially after braking down a hill. Battery on the screen charges well, never low or dead when I power her on. She is a trooper and got me across the country twice for college. I want to keep her, and don’t have funds for a new/decent used car.

Hoping for some tips. I can do a lot of repairs on my own (sparks, 12 v battery swap, MAF and throttle body cleaning) let me know what I should check first? Don’t have a voltage meter but could invest in one. Also bad to drive? I cleared the codes to see if they come back.