Am i ??????????????????????????????…

ok so im 18 ually active for 2 years with only one ual partener and have bin on the pill (estelle) for maybe jus over a year. on the 20th of july we had unprotected he came in me n all that n this was the first time we have done this so once i went onto my sugar tablets a week later it took about 5 days for my period to actually come so i was a bit late and then i had my period for 3 weeks i asked my mum about it n she said that it was probably becos i have taken 2 months of my pill( this was so i didnt have my period for my 18th birthday) and it was jus catching up so that finally went away since about saturday ive had really sore & and i didnt really notice how sore until my bf fort he might start playin with them ive started to think of all the weirdish things that have bin haooening n ive been really tired usually i can stay up till bout 11 -12 with no worries n now im struggling to stay up till 9 i dont wanna waste my money goin to the dr n buying a test if its not the case i jus wanna no wot is the chance of me bein pregnant?