Itchy vagina for days after sex

5 months pg had sex usually wear condoms except from when i got pg and the other day and no matter how many baths or showers i am itchin burning and stinging so bad down there started as soon as we finished as we didnt use a condom i can only assume its sperm that has caused this , any1 else suffering the same sypmtoms ...could i have gained an allergic reaction to sperm ?? Is this because i am pg ?? Or maybe as i have been on antibiotics recently ??? Please some1 tell me they have the same problem i feel abnormally sore itchy dry burny and do not want this convo with my doc !!