Larger example from the Bible again: Pharaoh.
God did not need ten plagues to set his people free. He chose ten plagues to show who he is. Dimwitted Pharaoh goes off and has his own version of free will for the first few plagues. Then, God, not being done with him or Pharaoh's peeps, THEN hardens Pharaoh's heart and continues on. So, no matter who freely chose, God got his will.
Your work problem:
As hard as this is to believe, God did not guide you go into that field of work because that field of work matches your college curriculum for what you should do after college. God has purpose for you. You specifically. His goal is to teach you two things in this life to prepare you with everything you need to know for eternal life:
1. God really, really, really loves you.
2. Trust him.
Your whole life comes down to getting those two things, so you will be ready for eternal life. AND eternal life means you get the privilege and joy of worshiping the Lord in all his glory.
There will be Pharaohs in your life choosing to do stuff that doesn't seem to be in your best interest. It doesn't matter. Ultimately, the Lord is going to set you free!
You will be Jonah -- fighting to stop God from taking you where he wants you to go. It doesn't matter ultimately. God will get you where he wants you to go. The only difference is which way are you getting there -- fish belly or ship?
You may have your stones-and-a-sling moments like David had when he faced Goliath. Cool, but ultimately, the Lord put you there to resolve that problem at that moment, and he's the one angling the trajectory.
This may be the one and only job you ever get in your field, or you might end up being very successful. No matter how that goes, that's God getting you to HIS goals.
When I was in my 20s, I too was thinking "career." I laugh at that now. I've had "careers." Quite a few of them, actually. Ultimately, I look back now and see why God did not let some perfectly good plans work out for me. I needed money. He needed me to be at the right place at the right time to help someone really important to him too -- my husband. (And hubby was tasked with taking good care of someone else the Lord loves -- me.)
Little did I know way back when that I wasn't really trying to figure out if being a housewife was my calling, it wasn't. I just needed to be home when hubby broke his back, so I could see that little want ad in the paper that would give us a place to live and something to eat, while his back mended.
When it did mend, we still had just enough to get by and get back on our feet again. And when we both got back on our feet again, who knew the most secure job in America -- a federal government job -- would end up not being secure at all. And who knew that while starting my own business, and hubby getting a free education to learn how to network computers, would end up with me becoming disabled, and then him being more disabled? Oh, yeah! God did! Because God needed me to be home, yet again, when hubby was on chemo, and then when hubby needed to be driven to the ER with a massive heart attack.
Honestly. A job is not why God put you on earth. He put you on earth to love you and teach you to trust him for eternity. All a job does is help you help others, put some food on your table, and a roof over your head, while you're in God's school learning his purposes for you.
Free will? Sure, you got it. So does everyone else. BUT God is still sovereign and decrees stuff that makes the entire universe work all the time just so he can have a people who will love and worship him eternally. Trust him. He's perfect at what he does. And he is working out even this per diem stuff out just right for you, no matter what your bosses think or do.