If you find on Reddit that on your account you can see the video, but if you logout of Reddit and then check the subreddit and can't see the post, then you have been shadow banned. Sometimes you don't know why, but it might be due to spamming. I'm pretty sure my whole channel has been banned from the subreddit "videos.". You can message the moderators and ask, but I never got a response back from the "videos" mods. On the other hand, the mods from "animals being derps" were nice and told me in one of videos that they removed, the dogs were too cute and not derpy enough. Just like others said, go slow and join the community. You will learn which subreddits work for you.