There are so many choices that it is easy to be overwhelmed. New gimmicks, which come and go over the years, can be very attractive but probably not as useful as their sales presentations are entertaining. Here are what I take to be "bottom line" considerations:
1. The ammo must function in your gun. I know that defense ammo costs more but you need to know that it's reliable in your gun and you should be well-practiced with what you carry. Some guns, especially little pocket guns, can be finicky with what you feed them. It doesn't mean that yours will. It just means that you need to know.
2. Understand the limitations of your tool. The LCP is a little pocket gun. It's nice for what it is but it still is what it is. That means it will probably be more challenging to shoot accurately, especially over distance. Recoil will be more pronounced. It generally takes more practice to master a gun like this one. Being a "newbie", that means an obligatory recommendation to "practice, practice, practice" and consider taking some real lessons above and beyond anything that was mandated by state or local government. That said...
3. Shot placement is more important than ammo selection. Dovetailing with the second point, .380 isn't particularly powerful and that's especially true from a short barrel. That's why you've got all that discussion about penetration versus expansion in previous posts. Regardless of how powerful a round might be or what it does once it connects, where it connects is key. Sure, seeing a gun can deter some attackers. Sure, having a gun shot at them can deter others. Sure, the trauma of getting shot anywhere can stop a lot more. The surest stop is the vital shot that physically disables the attacker beyond choice. So again: "practice, practice, practice".
On a lighter note,
have some fun! A great way to get a handle on real-world physics is to get out to the woods and shoot some stuff with different kinds of ammo. Obviously, phone books, water jugs, expired food items, or whatever else you want to shoot will not necessarily approximate the body of a bad guy. Neither will ballistics gel when all is said and done. That's not the point. It's more about developing an intuitive grasp of the physics of what you'll be carrying. That, and it's boatloads of fun!
Just remember to keep a safe distance, wear eye protection, be wary of rocks and other things that promote ricochets, and practice basic safety while you do it.