Signs of pregnancy early on?

I have been having for five weeks, and I just want to know what could be signs that I am pregnant this early on? We are always careful, as we use condoms and lubricant and I am very rigid about taking the birth control pill. Please tell me, what signs could I have of pregnancy if I could be five or less weeks pregnant? Also, last month I skipped the last row of my pill packet- the placebo (fake) tablets, and continued straight on to the first row of the real tablets in the next pack- could that give me any possible side effects?