Using photos, audio, videos of Adobe stock in after effects

The licenses for Adobe Stock can vary from unlimited use to very limited use. You just have to read the License information and purchase the license appropriate to your use. You'll find Adobe Stock License Information here.

You can use any image, illustration, or video you have created for non-commercial video production with any production software from Adobe or anyone else. If you use a photo or video or even a piece of music you play but did not write in any commercial project, you must have model releases for any people and location releases for any identifiable property. Taking commercial photographs or shooting videos in a national or state park requires a permit, but non-commercial photography is not usually regulated. "Street Photography" or landscape photography for "artistic" use is less regulated, but if you intend to sell or profit from your photography, you need to study up on releases and permits. 

Just creating a video for social media does not count as 'commercial' use, so there is little risk of running into legal issues if your work is original. 

I hope this helps a bit.