ろめたい(うしろめたい) Look back on and regret, now that you are older and wiser.
みる(かえりみる) Consider the consequences of some thing you ‘re about to do. Also to look back on – literally or figuratively. Good or bad. To reminisce.
(こうかい) Regular regret. Unlike 後ろめたい and 省みる、こうかい can be used about  something you did a second ago.   $$$
(はんせい) This is only used about the recent past. It means looking at what you just did and seeing how you could improve. You can use this even if you didn’t make a bad mistake. Like you got 80% on a test but next time you want to get 90%.   $$$
(ふりかえる) To take stock of your life. If you want to talk about taking stock of your life, reflecting on your present situation, without specifically regretting mistakes, you have to use this one.