For some odd reason the devs made the xp boost appear on your toolbar when it is still in your inventory. Making it very easy to accidentally use. Perhaps you did this? You wouldn't be the first.
To be safe, put these in your bank until your are ready to use them.
i noticed that. im not sure it intentional as thats pretty much how every consumable and toggle item in the game works, but it probably should be adjusted if possible as its too easy to click by accident.
my 1 hour boost is missing from one of my characters. I had it stored in my bank with the 8 hour one, but it's disappeared. I haven't used it, and stored it in my bank as soon as I got it. I've sent a GM ticket about it. I've definitely not used it, but it's gone.
My other character has both the 1hour and 8hour boosts still, but I'm glad I've checked. Thanks twenty_eyes for making me check!