It's gone from REALLY bad to MUCH MUCH WORSE for ex-NFL QB Trevone Boykin -- who's now facing shocking new criminal charges even though he's been locked up since November.
As we previously reported, the former TCU superstar has been in SERIOUS trouble with the law after he allegedly broke his girlfriend's jaw in an altercation in March 2018.
Boykin was out on bond while he was fighting the case in court ... but he was thrown back in jail in November after cops say he failed to charge his electronic monitoring device.