Apart from the scan, get blood HCG done at 48 hours interval to see if the levels are rising. Doubling levels are indicative of higher chances of pregnancy carrying forward.
It is common for some women to bleed on and off during the first 3 months. However, any spotting or bleeding in first trimester should never be ignored. It can be due to simple causes such as infection as in your case which could be persisting, cervicitis (infection/inflammation of cervix), vaginitis (infection/inflammation of vagina), or it can also be due to a part of uterine lining sloughing (due to incomplete D and C) or due to threatened abortion. Sometimes it happens without a cause. It can also be due to hormonal imbalance. Do discuss this with your doctor and get yourself examined for all these causes. Take care!