35y white female. softball size knot on left side of head just showed up. extremely swore but no headache. should i be concerned?

Yes: If you have a large mass that suddenly shows up like you should see a doctor immediately. It could be bleeding under the skin. If you are on blood thinners it is even more urgent...

Please seek help : It is difficult to comment without having look at this swelling. If you haven't injured yourself, this swelling could mean an abscess or a cyst. Please visit your GP for an examination and further investigation as it is abnormal to have such large knots appearing suddenly.

Yes: This is huge and something is going on. You need to be evaluated.