Hayes to White City £5.20 (off-peak as you touched in before 0630, assuming you went straight to the tube at London Bridge)
White City to Oxford Circus £2.50
Oxford Circus to London Bridge £2.40
Total so far £10.10
London Bridge to Hayes should have cost a further £2.60 to bring you up to the daily cap. After 1900 you get 2 hours and 5 minutes to make the journey so you shouldn’t have exceeded that, and Hayes has validators so you couldn’t be going the wrong way. If you touched twice in the morning they would have to have been separated by 2 minutes to makae a difference.
Journey history. Do you have an account set up already? If yes, login* and add your contactless card to it and you’ll be able to see the history. If no, go to https://contactless.tfl.gov.uk and scroll down to where it says 7-day journey and payment history. I strongly advise getting a proper account and adding your card to it because you can then see history for up to a year. If you look at the Journey history and queries page it shows how to contact them about a journey.
I have to caution about what you did. Had there been a revenue check at Oxted you would probably have had to pay a penalty fare for travelling without a valid ticket. My recommendation would be to travel by the next train to East Croydon, touch out and get a ticket to Oxted and use that to get back in. Upper Warlingham is the furthest you could go on contactless, but your train may not have stopped there so you couldn’t touch out. No need to queue for the extra ticket at East Croydon as you can purchase an e-ticket on your phone. End of caution.
*Logging into a TfL account can be a bit of a pain because they’ve screwed up implimenting the captcha code, but you should get in eventually. It usually takes two goes.