The maximum file size for picture/video messages depends upon the device's network capability. Here you can increase the file size limit to 1MB or set it to have no limit at all. You will see an option for “MMS Size Limit“. Once you’ve downloaded and installed the app, open it and select “Menu” > “Settings“.
ChompSMS can be downloaded from the Google Play. You could use email instead, but if you really want to use an MMS text message, you can use a third party messaging solution like ChompSMS. Sorry you cannot add this video to your message. The thing is - If you’ve ever tried to send a file larger than 300kb using the Messenger app on your Android device, you will likely get an error message similar to the following: