Just remember that the event tickets can drop from any random mob. So if you killed other things before the WB and didn't loot them, that might be what happened to the event tickets.
On the other hand, you can still contact Support if you think you are missing tickets. I missed my tickets on Friday because ESO became unresponsive during my first dragon fight. I used the Ask for Help function to make a report so I got a email response, and had to go back and forth with Support to clarify my issue, but they were able to refund my two missing tickets.
I've had the same issue, had tickets drop Friday circa 9pm, taking me to 10 tickets, then killed dragons on an off until 2:30 AM, Saturday afternoon brought the pet and my balance dropped to 0, then killed some more dragons 10pm-12am and no tickets dropped until Sunday night, 48 hours after my last one.
The Sacrificial Warriors GMXbox One EU:18x CP Chars (2300+ CP)Xbox One NA: 3x CP Chars (800+ CP)Xbox One (alt) EU:5x CP Chars (1500+ CP)Xbox One (alt 2) EU:1x CP Chars (450+ CP)PC EU: 1x CP Char (400+ CP)