Is this possible?

[The Borg]

Spoke Problem (part deaux)-

Ok...REI fixed the spoke for free! Cool!

But is this next part of the story possible?
When I first noticed my spoke was broke (rear tire)...I had received two flat on my last ride on my front tire. As I never was a fan of the tire I had on there...I replaced it at REI with the same tire as on my rear, and bought two new tubes.

BUT, today, on my ride into work, I got a flat about 10 miles out! Dang...what rotten luck. So, I just happen to limp into a gas station, and decided to repair the tube. I ripped out the tube, patched it, and put it back in and pumped up the tire (with the gas station pump air)...and off I rode.

Only to find that about three miles later - I got ANOTHER flat! My air was leaking out...I limped into work. At lunch today, I take my pump and put some air into the tube to find the leak...submerge it into the sink an viola! ...no bubbles? There appears to be no leak. Is that possible? What gives?

(Other factors: My last ride a few days ago...I had two flats on the same tire. Prior to todays ride, I bought two new tubes and a new tire. Only common thread is that I had a liner that I used last time, and I also used today. To eliminate any possible little stuck thorn tip...I'm removing the liner and going to see how it works today on the trip home)