If you are happy with your current situation or not. If you are rich or poor, healthy or sick, positive or negative mental attitude, confident or timid, rational or irrational. There is absolutely nothing you can do about your current state.
The only thing you can control is the future.
Do you get that? Wherever you are right now is where you are. It is already too late to make any changes. Let's not even get started about the past, if you are a person that believes they can change the past then I don't know how we can have a reasonable discussion.
Anything that happened yesterday, a week ago, a decade ago, a millennium ago and where you are right now are equal in your ability to change them. These are events that are done. I would suggest spending maybe 1% of our time contemplating the impact of these events, unless you are trying to learn an lesson to change your future.
I suggest we spend 99% of our time, effort and thoughts on the future. What is going to happen in the next hour, day, month, and years. This is the area where we have the ability to make changes.
For those technical minded, it is the same thing as flipping a coin. If you flip a fair coin that has a 50/50 chance of landing heads or tails and you flip it 10 times and they are all heads, what is the chance that the next flip will be heads? Of course, it is 50%. It wouldn't matter if there had already been 100 heads in a row, the next flip is always 50%.
I do realize that we aren't coins and our past actions will impact our future potential. If you are uneducated and then decide one day to enter a profession that requires a high level of education, you will probably have to exert more effort than someone who is already educated. If you are obese, don't expect tomorrow to run a marathon. The key is that just because you were one way yesterday, or right now, it doesn't mean you have to be that way tomorrow, next year or in 10 years.
People often overestimate what they can accomplish in 1 year and underestimate what they can accomplish in 10 years. Leave what has happened in the past, in the past, and think about where you want to go and how you are going to get there in the future.