is my gf pregnant

so my girlfriend and i have started having sex about 3 weeks ago and i have been using condoms and on broke but i pulled out before and we didnt use one 2 times this was at the beginging of the last three weeks but a week ago her breasts were tender and that went away like 3 days ago and she is due for her period in 6 days but she started bleeding yesterday and to her its a normal flow but last night she got nauseus so i dont know if she is pregnant or just was sick and being a eek early is just because she started school a month ago and she is on an all girl floor. its to early to test but can someone give me some words of encouragement please im only 20 and shes 18 were not ready for a baby so help me please.