Is my dog aggressive? Help!

This sounds like fairly normal - inappropriate, but normal - behavior for an excitable adolescent dog. Just like human teenagers, adolescent dogs can have trouble with self-control, rude behavior, pushing boundaries, and just generally being obnoxious (I say this with love, mind you, my youngest pup is only just starting to get over this stage).

Without seeing it, it's hard to say whether the 'smiling' is just how his face looks (a lot of Frenchies just look smiley a lot) or he's offering you appeasement signals - basically saying "I don't like this yelling please stop". Don't mistake this for guilt - many dogs don't actually understand why they're being yelled at, but will still offer these signals because they're uncomfortable or scared. He may or may not be connecting the yelling to the unwanted behavior - again, I can't say for sure because I haven't seen the interaction for myself (and also I'm just a dog nerd, not a professional trainer/behaviorist). Humping is a normal behavior in overexcited dogs, and just a way they blow off energy when they don't know what else to do - it's not a sexual behavior, just a rude one.

My first bit of advice is to create a safe, confined space for your pup where he can go when you need a break or know he's going to misbehave, such as when visitors come over. This could be a crate, a pen, or a dog-safe room blocked off by baby gates. You may want to block him out of the living room (or wherever the sofa is) entirely unless an adult is there supervising and working on training good manners until this is under better control, so you and your kids can relax. This is not a solution, just management to prevent him from practicing naughty behavior and give yourself some breathing room so you can take the time to work through this behavior without having a breakdown (been there!).

As to solving the problem, how much mental and physical stimulation is he getting? Your first step is to make sure he's getting exercise and training, games, or puzzle toys to occupy his mind and make sure he's not bored. Bored pups get into more trouble. If he gets plenty of exercise and brain games, you can look into training him to settle. Some dogs just don't understand how to relax and chill out at home, and they have to actively be taught it. Look up Karen Overall's Relaxation Protocol or Margot Woods' 'Sit On The Dog' technique to get a good idea of where to start! Confining him with something like a stuffed food toy (like a Kong Classic) or chew when you need him to calm down is also good practice.

Hi again @Jenni2010!

I'd definitely set up some kind of pen or crate for your pup so you have somewhere he can be where he can't get into trouble. Many dogs take a while to learn household rules, and need help understanding human concepts like no peeing indoors and how some things aren't for chewing.

Essentially, when you can't be paying close attention to him and interrupting or redirecting inappropriate behavior, he goes in his crate/pen/puppyproofed room. When he's out, you're watching him, taking him out frequently to pee (and rewarding him when he goes outside), directing him away from things he seems to be sniffing too intently (marking behavior), and redirecting him to appropriate chew toys when he tries to put his mouth on something off-limits. Additionally, it's important to make sure he's getting mental and physical stimulation, so his behavior isn't exacerbated by boredom. Clean up any of his pee spots thoroughly with an enzymatic cleaner designed for pet messes, so that even he can't smell old accidents and think that it's a great bathroom spot.