petrol in my oil.

[normnxn]

petrol has gotten into my oil. the whole tank has emptied into the oil. just been trying to find out where a drip of petrol was coming from on the bike. and noticed that from the oil screw there was leak. the bike has been giving me problems starting like the spark plug wasnt working, so i changed the spark plug and thats when i noticed the petrol leak. i dont know how this has happened or what to do next but i have drained the oil. can anyone help?