It was not too long ago that I, too, made the transition from hiking to trail running. The cool thing is: one isn't superior to the other and you can do both.
It doesn't have to be a crazy change between the two. It can be a natural and somewhat effortless switch.
Here are a few things that will smooth the transition:
1. Remove the expectation of how long a trail run will take. A trail run is much different than running in your neighborhood, on a track, or on a treadmill. As you know, trails have varying terrain, obstacles, rocks, dirt, mud, sand, trees, bushes, and potentially wildlife. Trails also have a vast array of climates. One minute it may be 75F and sunny, the next it could be 40F and raining. Running on a trail WILL take longer than you anticipate. Give yourself plenty of time to ensure you're not feeling rushed.
2. Hike the ascents and run the descents. Many trail runners take on this approach. I used to think that if I didn't run the entirety of a run, it wouldn't be considered a true run. But hey, guess what? Whether you run the whole thing or a combination of hiking and running, it's still a run! Hike the hard, run the easy(er). This will also help you conserve your energy instead of getting completely gassed out on the ascents.
3. Wait to buy trail running gear until you know it'll be worth the investment. Your hiking gear will work just as well for your runs. Would a hydration vest perhaps feel better while running? Sure. But for your first few runs of seeing if you enjoy it, stick with your light hiking pack before dropping $100+.
Bottom line: enjoy your run just as you enjoy your hikes!