Well, he's still really little, so don't worry about creating bad habits or anything! He might just need the help to go back to sleep for now.
What I've heard (but never tried) is to try going in just before you think he's going to wake up, and then tickle/pat/nudge him. Not enough to wake him up, just enough to get him to "notice", if you know what I mean. Apparently it resets their sleep cycle and they go on to sleep for another cycle. Hopefully someone else who knows more about it can come in here and give you better advice about it!
And babies change their sleep habits a lot, so be prepared if that does happen. It is completely normal! Chloe slept through the night for a couple of weeks, and has never done it since.

(She doesn't sleep that badly, by the way, I'm not trying to scare you!

)
Edited by MissShell