So today I started masterbating after I had orgasm , I went down to whip myself I spotted some blood on the toilet tissue, I thought I just start my period but usually I start cramping before or it continues bleed and then I cramp but this time neither happened, my period doesn't start after 20 days in a month.. Days before Valentine's I did had sex no condom ONCE !. But after I've been craving like hell and really tired. Could I be pregnant ?