I dont feel worthless.
I'm somewhat of a determinist myself.
Everything we do, is all we could do, whether it be one thing or another I do not know yet what I will freely choose.
God determines all events and freewill actions to take place. He is in control of all.
God forsees the freewill actions of man, and he determines them to come to pass, as without him nothing would come to pass, he determines that that pass. He is in control, determining all, yet man retains freewill in the sense that, for example, I choose earlier to drink orange juice, of my own freewill, and God who foresaw that determined of his own will to actualize such to occur.
As we can see, while God determines everything and nothing goes under his knowledge, we retain freewill, the origin of our choices is us, not God, yet he determines our freewill to come about.
Besides, even you must admit, what you have done, that is what you did, you cannot change it. What you will do is what you will do, you cannot change what you will do, but you can change what you will to do. If you choose to use the bathroom later on, you will choose that, and there is nothing that can change that on the condition that you will choose to use the bathroom.
Not so pointless.