You can use candid peasant in vagina for the infection part, just take precaution to not insert it too deep. Regarding the drugs prescribed to you they are safe only except chymoral forte as there isn't enough evidence about use of this drug in pregnancy. Please do visit your gynaecologist once and review the need of these medications. Duvadilon is not preferred these days because of entry of more safer and effective drugs but some gynaecologists still prefer and continue giving it to prevent the pre term labour. So it's totally at their discretion.