This has completely foxed me. DH got a new tablet for Christmas and decided to set up a Twitter account. I helped him put a profile pic on it and showed him the basics - he's now following lots of people but hasn't tweeted yet.
He's just come through to tell me his profile pic is on someone else's posts. I've just looked and it's not showing in this guys profile, just his posts appearing on DH's timeline, his profile is still an egg. And odder still, the pic doesn't show up when I look at the Twitter app on my iPad, my android phone or on the laptop, he's an egg there too!
I think this suggests it's an anomaly in the Twitter app DH is using, but have never come across it before (kind of hoping it sorts itself out) but it's a bit disconcerting. Has anyone come across it and did it go away on its own?!