Pregnant or Not ? NEED ADVICE LADIES.

Okay Ladies, I need your help!

My eve is ALWAYS spot on, from start date to end date, and it's been a long while since I've missed a period or have gone off track...

My last period was on Oct. 6th-11th, and I was supposed to start on Nov 11th til the 16th, but I am now 18 days late.

Me and my boyfriend had sex about 2-4× during my fertile week and around ovulation.

Around the time of my period I had brown dishcarge mainly only when I wiped. I've been very emotional (I wanted to cry when someone told me I couldn't go to the store), and the past couple of days I've been getting sick, mainly when I'm smoking a cig. or don't eat when I'm hungry. Frequently using the bathroom (to the point I almost piss on myself) and quite a lot of white/clear discharge.

Usually I'll get sore boobs about a week before I start my period, but there was nothing! No sign of a period or anything.

I've taken a variety of different test, taking them from early in the morning to really late at night but they've all came out negative except one that had a very very very faint positive line.

Can anyone give me an idea of what's going on or what to do?

I don't want to get my hopes up just yet....