How To Confirm Pregnancy?

Lmp 28/1/2015 At 28/2/2015 i get another menses but for 2 days only At 11/3/2015 i get bright red vaginal bleeding without any pain sooking one pad after that little brownish discharge Beta hcg done at that day =194 Scan done abdominal no thing appear and thin endomtrium After 48 h beta hcg fallen 54 Im on duphoston and folic acid The qeustion is im pregnant or miscarge And continue duphoston or stopp