The Taurus PT-25 is a very small handgun that fires a very small cartridge (.25 ACP). For what it is, it's not a bad gun. I've shot its smaller brother, the Taurus PT-22, which is chambered for the .22 LR cartridge, and it's a fun little gun for plinking at the range. But this gun and others like it are better served as a (last-resort) backup gun rather than as your primary concealed carry gun.
In the end, any handgun is much better than no handgun -- just the presence of a handgun, regardless of caliber, can oftentimes defuse a situation and cause your attacker(s) to flee. That is of course the best outcome when placed into a situation where you need a gun to defend yourself. However, if you do end up being forced to fire at your attacker(s), the .25 ACP cartridge just isn't all that effective. That said, .25 ACP is certainly lethal with good shot placement. However, this cartridge is simply too small to reliably and quickly stop even a single target in its tracks.
There are guns that are essentially the same size as the Taurus PT-25 but fire a cartridge that is much more suitable for self-defense. Generally speaking, .380 ACP is the smallest effective self-defense caliber, but 9x19 (standard 9mm cartridge) is an even better choice. The .380 ACP is 9x17. It actually is 9mm in diameter, same as the standard 9mm cartridge, but is 2mm shorter, at 17mm versus 19mm long. The extra length for the standard 9mm cartridge allows both more gunpowder and a heavier bullet, and as such is more effective for self-defense. But because the diameter of the cartridge is the same as in a .380 ACP, the overall size of a 9mm handgun versus a .380 ACP handgun can essentially be the same.
What I'm trying to say is that why go with a subcompact .380 ACP handgun when there are subcompact 9mm handguns that are the same size? Not only that, 9mm ammunition is quite a bit cheaper than .380 ACP because of economics of scale -- many more 9mm cartridges are manufactured and sold, so they are cheaper than the .380 ACP cartridge even though they use more metal and more gunpowder.
Now, let's take that thought one step further, and compare a subcompact .25 ACP pistol with a subcompact 9mm pistol. There are great 9mm pistols designed for concealed carry that are not much bigger or heavier than your Taurus PT-25. For example, the Kahr PM9 has an overall length of 5.60", height of 4.30", width of 1.10", and weighs 16.7 ounces empty. The Taurus PT-25 has an overall length of 5.25", height of 4.30", width of 1.13", and weighs 12.3 ounces empty. Less than 1/2 of an inch longer and only about a 1/4 pound heavier, and you get a gun that is much more effective for self-defense.
Again, any gun is much, much better than no gun. Also, if you get enough trigger time at the range with your Taurus PT-25 so that you can reliably and quickly place rounds where they need to go, it can work just fine for self-defense. But why go with a .25 ACP concealed-carry handgun when you can get a 9mm concealed-carry handgun for (essentially) the same size and weight?