thank you for your pregnancy
Petroleum jelly is by no means an effective spermicidal agent or a reliable contraceptive
It is merely a lubricant, known to have certain effects on sperm, but it is most unwise to rely on using petroleum jelly to protect against pregnancy.
Also, with unprotected vaginal intercourse, you definitely run the risk of being pregnant, specially around the time of ovulation.
Please use a reliable, long term method of contraception
in the future.
If you skip your period, take a pregnancy test at the earliest.