I live in Indiana. My prev. landlord entered my apartment on two occasions without notice. I have a wittiness for both occasions. What can I do! Can I take her to court? She is trying to collect debt from me! If she takes me to court can I counter sue?

Sue for what ? Was she the landlord when she entered, or was she no longer the landlord, if she was not the landlord and entered, you call the police for breaking and enternig.

Normally a notice has to be given, unless there is a outstanding reason.

If you owe rent she can sue you for the money, I see no counter suit.

Her entering may be grounds to break your lease.

You did say PREVIOUS landlord, right? Did she sell the property to someone else? Did she keep a copy of the keys after the sale? If she does not own (or manage) the property then this was an illegal entry and should be reported to the police and the current landlord.

But I don't see any grounds for a suit, unless she damaged some property of yours.