first off, you need to settle down a bit. It just looks like you peeled back the cover a bit. By the looks of your gear oil it might be time for a change too. Do a search for how to change your gear oil. Get some RTV and do it up right. You should be able to do this for under 20 dollars.
second, if you think the oil is leaking from the pinion then you can replace the pinion seal. It's not difficult, you will need a breaker bar, or an impact to get the pinion nut off as it should be torqued to 170 ft. lbs.
Search feature is great. I also recommend how to sites like:
Daily Driven TJ
best of luck to you in your inquiries.