[Supras] Help with wife's Chevy Venture

[D P]

I needed to fix my wife's 02 Venture so that she doesn't complain about having to cramp my 3 kids in my supra while her van is down.
 
I replaced a leaking FPR and now the CEL is on. I had it checked and reset at Advance Auto Parts. Code is P0135 - Oxygen Sensor Heater Circuit Malfunction Bank1 Sensor1. They told me I have a bad upstream 02 sensor. The light came back on about an hour after it was reset.
 
My question is, is it a coincidence that the sensor went bad right after? Or is there something else I'm missing? The vacuum hose that attaches to the FPR was loose so I had to replace it. I also broke the hose that attaches to the PCV valve but fixed it.  Could it be that one of these hoses have a leak?
 
The 02 sensor is ~ $60.00. I just need some help to diagnose this before buying it. I'm thinking of replacing the PCV hose that I fixed but was wondering if I can get some more help here.
P.S. She's driving the van instead of my supra but is still complaining that I should've taken it to a mechanic since she thinks I broke something else after fixing the gas leak.
 
Help! Please!
Darren92T 5-Speed White PackageCanadian Model in Florida
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