improve advice?

You lost three games. That just happens sometimes, wait until you get a 14 game lose streak with some S+ ranks in the middle.

Probability is an odd thing, and winrates only smooth out over a huge sample of games.

Also, that tryndamere was garbo.

You died too many times in the first two. Can't give specific advice without seeing the games but you should pay more attention to what's getting you killed and ask yourself how each death could have been prevented. You should get into the habit of doing this every time you die and avoid writing it off as a teammates fault if you can. Sometimes it really is a teammates fault but more often than not it's your own mistake.