Advice wanted please!

Thursday 11th Feb I finished my pill after being on it since the age of 15, (I am now 23), Wednesday 17th Feb was the final day of my period, Thursday 18th Feb my husband and I started TTC baby #1, Today Sunday 21st Feb I have experience light brown spotting and have tender breasts, I am also having dizzy spells and a loss of appetite. Is this the beginning of my real period? Surely it's too soon to be symptoms of pregnancy?