Rpm and mph problems help please ?

Well I have a 02 oz rally lancer an just two days ago started driving funny it wouldn't past 70 mph an when I would give it gas it would just rev high but feel like its boggin down but never over heated an always ran at good rpms when I drove 70 but hear today it won't go past 30 mph if that an won't go past 4 rpm bogs down when I try just to rev it in park its automatic by the way what's my problem help please