I am going practical here:

Apply for unemployment on Monday. You will receive it! Both this employer and your last employer pay unemployment insurance and you have every right to collect it. They said you were not a good fit, and did not give you feedback as you learned. This is not a "legal" (you did not steal, cheat, etc) reason to fire you. Therefore they have no leg to stand on to fight and most likely do not have any interest in fighting it.

You should be insured until the end of the month - call the insurance company and confirm this. Then cram in as many appointments as possible before the end of the month.

Do not let this stop you! Take the weekend to be angry, then on Monday put on your happy face and get out there!

My best to you Mustang.