How can I send someone a text with a video?

So I record a video with my phone but I can never send a video message to someone. Every time I try to send a video message and try to pick the video I get an error message saying the video is too long and needs to be edited. I always have to edit the video and say if I were to record a 30- 60 second video only 8 seconds is what I can send. Why is this and how can I fix it so I can send my full video?

Also- Sometimes I try to email say a 3 minute video I got off the internet to myself but I never get it. I get a text message coming from my email but the attached video is never there. Why would this be?