If players are going to get injured, now is not a terribly disastrous time. There's quite a bit of time left in the summer before Tottenham Hotspur return to preseason training and a lot of time until the Premier League season resumes. But Harry Kane is hurt, so it's okay if you freak out.
. @hkane28 was a 79th-minute substitute but unfortunately limped off four minutes later as England U21s beat Wales 3-1 in Swansea tonight.— Tottenham Hotspur (@SpursOfficial) May 19, 2014
Obviously, there's a bit of good news here and one thing to remember. That bit of good news is that he left the game under his own power. And the thing you need to remember is that this was a U-21 international, so Kane would have left the game if he felt anything at all.
On the other hand, this is Harry Kane getting hurt, so OH GOD PANIC.
We'll do some digging and hopefully have more information for you soon.