Please help! Stressing 😞

Hello ladies. I'm in need of some advice so here it goes. I start my new job on Tuesday super excited as its my dream job! Well I've just found out I'm 4weeks pregnant!! My probation period is 6months. I'm so so scared of telling my new boss. I'm going to ask if my probation can be dropped to 3months because we are in fact applying for a house and the bank would feel better about giving us the money if I was in a shorter probation period. Anyways I'm just wondering if anyone has also gone through this and can help. Thank You xx