Having regrets also has a benefit. It will remind you how painful it is not to take action, it will remind you how painful it is to let opportunities pass by. It will remind you that taking risk is not scary at all and it is ok to fail, it will remind you that once you take the chance then you will not feel any regrets and you will still feel good because you were able to discover the answer.
If you have a lot of regrets now, take it positively and just make it a reminder that you don't have to waste time, you don't have to waste any opportunity because it may not come again. Opportunities may just come once in your life so you must devour it once it is there, give your best and give life a good fight
Make your regrets a reminder not a depression, remind yourself that you can't take any second for granted and you must try and take actions even if the chances of winning is very slim.
Accept regrets and treat it as a lesson, it happens to make you a better person. All you can do is live in the present and not from the past. Once there is an opportunity, even if it is scary, grab it and make it yours, fight for it and never let it go. Never let fear control you, never let it stop you. Just focus on making baby steps and always think positive.
Your regrets can only be erased once you learned from it and you are not letting any presented opportunities pass you by. You should always be alarmed if you are being lazy, scared and procrastinating because you are wasting a lot of time and those times will not return to you anymore.