The entire reason we can think and analyze at all is because of fear. Fear is the emotion of the past.
Reviewing your past show you what? That you are not perfect ever, of course. You made horrid mistakes and some lesser mistakes. You are busy right now making mistakes. Duh!
The counter for fear is courage and desire, e.g. anger and desire.
You are filled with free will and the ability to earn wisdom and grow. You need courage to face the world as an imperfect being and desire to guide you to more growth, next steps. Invest in these other emotions and embrace your fear.
Fear is good. Anxiety is good. But all emotions are motivators. Best be afraid to miss life by worrying. Get on with it!
Because it reflects into the future?. Everything bounces around sometimes.
If past was bad you could think things won't get any better... maybe discounting any options and so on, ignore the more positives and possibilities.
If past was good you could be afraid of it slipping away.. or that things will just go bad.. etc.
Reminds me of this..
"We never keep to the present. We recall the past; we anticipate the future as if we found it too slow in coming and were trying to hurry it up, or we recall the past as if to stay its too rapid not to belong to us, and do not think of the only one that does; so vain that we dream of times that are not and blindly flee the only one that is.
The fact is that the present usually hurts. We thrust it out of sight because it distresses us, and if we find it enjoyable, we are sorry to see it slip away.
We try to give it the support of the future, and think how we are going to arrange things over which we have no control for a time we can never be sure of reaching.
Let each of us examine his thoughts; he will find them wholly concerned with the past or the future. We almost never think of the present, and if we do think of it, it is only to see what light it throws on our plans for the future.
The present is never our end. The past and the present are our means , the future alone our end.
Thus we never acually live, but hope to live, and since we are always planning how to be happy, it is enevitable that we should never be so."
I do agree about it being (unconsciously) a projection of the future, so you automatically read it as "that's how it was then, it's gonna be that way in the future". If it was a bad memory then it's obvious why that'd cause anxiety.
When I experience this regardless of whether the memory was good or bad, I've just started to figure it out, but it seems to be a fear of not going anywhere. Like just...existing but your life is stagnant from however many years ago that memory was. I think it's subconscious but you have an assumption of where you are in life, who you are, and somehow the memory contradicts that which in a way is contradicting your sense of self. And it feels like it's pulling you backwards, or keeping your sense of self frozen in time. So it's like an existential anxiety. At least, that's how I experience it.
The past is our anchor. The place we need to visit if there's no other way to go.
But if this place is corrupted you will feel anxienty and desperation.
It's hard to see this corruption with the conscience mind because it has it's place in the subconscience.
You have to find out why the subconsience might have corrupted the memories (the good ones and the bad ones) which can have several reasons.
One being the thought: "This will never happen/will happen again.". Or: "This wouldn't have happened if.../I missed this opportunity.".
You can clear your subconsience from this thoughts by finding out what secretly bothers you and after that eliminating this wicked thought.
It isn't easy but I'm certain that you can do it.
In some ways, the past is a story we tell ourselves. Our memories are not always accurate either. In addition, there will be parts that you highlight in your mind and parts of your past experiences that you forget or miss and that might have brought balance. It can be helpful to look at your memories through a more detached lens.
To answer your question though, it really depends on what sort of meaning you are attaching to your past memories. What are you making them mean? I can see them causing anxiety out of regret or a lack of closure over something that happened that you had no control over or (positive memories) missing the good times and feeling anxious that you can't go back there.
The interpretations are endless. What creates anxiety is a lack of acceptance about what was or what is in some way. Ask yourself what stories you tell yourself. What are you making your past experiences mean? Could there be something you did not consider? There are always ways to find closure and healing in these things and to embrace the present head on, to be full of hope and faith rather than anxiety. Maybe you need to forgive someone, maybe you need to forgive yourself or both. The answers are inside yourself.