Recap time! Just for context, I've only been watching this show for just over a week so I have no idea what I'm talking about. I've been getting some background info from some very helpful folks on Twitter whenever I'm watching (come play! @SerialDrama) but otherwise my entire frame of reference is just my very occasional visits over the years and general awareness from soap magazines and the like.
Here we go!
Will is hanging out alone and having flashbacks to Sonny and Sami trying to explain who he is. This involves grimacing.
Sami spent the night in jail and is very grumpy about it. It's because she punched Susan, which was awesome. The attending cop finds her whole story pretty hilarious. Marlena shows up.
Paul is sitting at the bar where Will works, which has literally never had a customer but apparently has no problem with people in emotional crisis hanging out there and never ordering a damn drink. He leaves a voicemail for Will. Paul is sad, and John shows up to hug him.
Will asks Susan if she's really his mother.
Marlena is delighted to learn that Sami punched Susan. Sami mentions that Paul knew Will was alive and didn't tell anyone, but I feel like I need to point out to her that he only knew for sure for one whole day and under the Soap Code of Ethics keeping a secret for only a day is practically a qualification for sainthood. (I'm sorry, I'm sorry, we all know who the only true soap saint is, Praise Jaysus.) John is congratulating Paul for coming forward with the truth, but Paul thinks he should be ashamed. (Paul is a long-lost-heretofore-unknown-son of John, right?)
When Susan shows Will the (very minor) black eye Sami gave her, he accepts her insistence that he's not Will. But he wants to go out and prove that he's really EJ.
Eli is at the crime scene where JJ shot Theo (thank goodness someone's finally doing some police work around there!). Gabi delivers some expositional dialogue explaining exactly that. Rafe shows up looking for Hope, and these scenes are way too short.
Adrienne asks Sonny how Paul is handling this, and he says that he doesn't know and doesn't care, which doesn't seem very nice!

Paul tells his dad that he'd kept the whole "Will is alive" secret and how he can never forgive himself, while Sami fills Marlena in on the whole madness with Will thinking he's EJ. Will confronts Susan about why there's no computers in the house, which she insists is because computers aren't good for "growing boys' brains" and I'm wondering how old Will thinks he is. He's very young looking, but this is pushing it!
Sonny tells his mother about how Paul kept the Will secret, while Paul tries to explain his reasoning to his dad. (Today's theme seems to be "everyone checks in with their parents.")
Rafe tells Gabi that Will is alive, and she's delighted. I don't have the slightest idea what either of their relationships are to Will, there's so many damn people on this show!
Marlena asks how Will could possibly believe that he's EJ, making Sami his ex-wife, and Sami again goes through the hilarious litany of why Will can't possibly be EJ: it's because EJ is British and tall and straight and dead. I always feel like the loved ones in these soap back-from-the-dead stories don't take enough time to bask in the ACTUALLY REALLY MIRACULOUSLY GOOD NEWS that the person is alive because they're so immediately outraged about amnesia and solving problems. Sami! Take a moment! Breathe a little! Your dead son isn't dead! Speaking of her dead son, Susan is showing him a bunch of "proof" of his EJ-esque childhood. The reason he can't see the date on his birth certificate is because he was a very messy kid with bananas and eggs!

That sounds like a very real thing, since most parents let their children play with their birth certificates while eating! I've rarely had a dinner without the whole family's birth certificates on the table! Isn't that what they're for?
Marlena explains that she and Sami got past her affair with John, so Sami and Will can get past this, which doesn't make the slightest bit of sense as they are possibly the world's least comparable situations?
Susan tells Will all these people are scamming him because they want to get their hands on the DiMera fortune which.... Susan and Will don't exactly look like they're living large?
Paul: Will's lapse in judgement might be the thing that pushes Sonny back into Will's arms!

I legitimately have no idea what he means by that.
Sonny doesn't understand why Paul is being insecure since he and Will were separated when Will "died." But then he says he has to make Will remember who he is and what they had together, so gee, I wonder why Paul is insecure!
Okay, so I guess Gabi is Will's ex and the mother of his child? Rafe explains the whole amnesia/EJ sitch which Gabi responds to the correct way, which is to be concerned but moreover VERY HAPPY THAT HE'S NOT ACTUALLY DEAD.