Ok, I am asking help, I am not sure if it is time to send the machine to the professionals to fix. Last night, my daughter was using my Brother SE400 and jammed it badly. I got the jam out, but had her tighten the screws back for me on the machine. Now I think the screw may be off the thread cause I can't get it back out. Should I take it in and get someone to look at it or wait until someone else comes along with more hand strength and let them try it.

I don't know what is best for this, but I hope you figure it out soon. Had when you can't sew.

If it doesn't come out with steady, medium pressure you could strip out the screw and end up with a bigger repair bill.

Which screw is it?
If that's all that's wrong and it's not in an important spot, I'd take it out myself. you can always buy another screw cheaper than paying for a repair.
But maybe you shouldn't listen to me.....lol.

Put some ice in a plastic bag and hold it against the screw. Sometimes the metal will reduce (can't think of the word that is opposite for expand) in size just a tad and it might be enought to get the screw out without damage.

Which screw was it? The ones in the plate or the needle? The needle one I use my rubber gripper from the kitchen to loosen it if it is stuck. The screws on the plate you could put a drop of machine oil on them and wait a few minutes to try again. If still stuck and you need to get in there, I think a visit to the repair shop might be in your future. If you don't need to get in there, run your machine for a while. I find that the vibration of the machine sometimes loosens the screws.