How do I find out if a criminal complaint was filed and charges made against me?

You would have to wait to be contacted by the District Attorney or Detectives on the case

My standard disclaimer: I am not offering legal advice, assume I do
not know the law in your state or at all for that matter and that I am
just making suggestions for starting points for when you do speak with
an attorney. Do NOT rely on anything I write and contact a lawyer in
your area immediately after reading my posting.

Time will tell. It is probably not in your interest to make noises about this incident by contacting the police or DA's office. They are far more likely to drop it if you lay low.

Based on what you've said here, there does not appear to be any jeopardy to you (loss of evidence, delay in critical investigation) if you wait. If you have a belief that some evidence in YOUR favor will be lost if you don't get on it quickly, then I would advise that you hire a lawyer to find secure that evidence now.

Otherwise, no news is good news.

You should contact a local bondsman and make arrangements with that company to regularly check to see if there is a warrant for this complainant.

You are correct in your concern that a new case could cause problems with your informal probation if charges are filed.

If a case ever gets filed you will be notified of the charges. Good Luck!

Well, the good news for you is that criminal records for Los Angeles County Superior Court can be found online at http://www.lasuperiorcourt.org/. All you need to do is go to the website every morning and look up your name and date of birth. This will show you if a criminal complaint has been filed against you or if there's a warrant for your arrest.