This warning shows up if you have been reported multiple times and yes you can get problems if you are getting reported in the future.
This is basically the first stage out of three that occur after multiple reports. The three stages are:
- Warning message (the one you got)
- Chat/Ranked restriction
- Temporary ban (up to a month)
Now to prevent innocent people from getting banned or restricted the warning message exists (There are always people who report everyone if they lose and sometimes you're unlucky and have 3 of those in a row). However if you recieve a Chat/Ranked restriction or even a ban you probably are a toxic player (or you have a really bad day) since it requires multiple reports in a row.
Getting banned is extremely rare but it can happen to the most toxic players in the community, and I'm talking about the constantly flaming and insulting ones.
If you are no tilter or flamer you shouldn't be too worried, however if you do show your frustration in chat you might want to try not writing anything at all while communicating via pings. Everyone has bad days and gets frustrated sometimes but instead of criticizing someone you should either try to be positive or neutral.
Compliments and a good attitude will also boost the team morale and further increase your chances of winning.