I have been ttc for 4 yrs now, i recently just started seeing an obgyn i had an HSG in november, everything has came back normal, i am 20 yrs old, i wasnt really concerned with getting pregnant this last month, i just noticed my period is over a week late, im having slight pains in my right side, gas, tired often, tightness in my stomach, back aches, ive had a non stop headache for 2 weeks, is there a chance i may be pregnant?