Whats the first sign of a chronic hematomo and how bad is the headache i just feel like i cant focus hit head a month ago urgent care said mild concus?

A CT Scan: of the head to rule out a hematoma is the test to determine it. Please ask your doctor to order.

Go to the ER: If you are still having symptoms 1 month after a head injury and you didn't get a CT scan then you need the scan. It is unlikely to show obvious injury but if it does that's a big deal. Rule of thumb is that if you didn't get knocked out, remember the entire event, have a normal neurologic exam, and were not intoxicated then you are probably OK. Your problem is still acute, not chronic.