Every time i leave confession and get communion I always am scared that I’ve done it unworthily. I can’t prove to myself that I did, but it’s always in the back of my mind. My question is this-do people who say a bad confession or recieve communion in mortal sin know for sure what they’re doing, or are there instances like me where they think they’re doing everything right but still do it unworthily? …Or am I being too scrupulous?..
Any of you feel the same way?
I think you are being too scrupulous

and it seems these scruples are a distraction for you. If you go to Confession and don’t
intentionally hold back your sins from the priest,
you are forgiven. Try to trust in God’s mercy… distrust really distrances us from Him.
If you have mortal sin, go to Confession. If it’s venial, say an act of contrition and ask for God’s mercy during Mass. Then, focus no more on these sins, but consider what happens at Communion: you receive Christ into yourself and He unites Himself with you. This is an occasion of joy not only for you, but for Him also. Don’t doubt His forgiveness… trust in God’s mercy, thank Him for it, and go and receive Communion with peace.
I used to struggle with this same thing and sometimes I still do, but it really does tend to distract us from the reality of the Sacrament. I’m sure God sees your good intention: that you want to receive Him worthily - but in Communion, focus on loving Him and not on your sinfulness. Give your sinfulness over to Him, and let Him forgive you, and absolve you by the hand of His representative.
Don’t ever doubt Confession. If you withheld anything from the priest, you
would know it, cause it’s an intentional act and not accidental.
God bless