Daniel Keane, from Chaddesden, sobbed so much during the proceedings that the trial was temporarily halted.
His barrister has said that he is “having a hard time in prison”.
Keane had been on a suspended sentence when he entered his partner’s home and assaulted her.
This included punching and biting his partner.
On the night, she told him not to come back to the property, which led to him hurling abuse at her from outside the house.
Derby Crown Court heard how she then took pity and let him in, where he proceeded to pull her hair and bite her whilst she was also 6 months pregnant.
Judge Robert Egbuna took into account a letter the woman wrote where she was said to forgive her partner.
Egbuna had little sympathy for the defendant however, as he handed him a custodial sentence for his actions.
The judge said: “You need to stop crying in front of court. Your partner is here, she is the one that should be crying.
“You behaved like a coward. You entered her house and beat her up for no reason. You weren’t crying when you beat up your partner.”
The defendant’s lawyer Mark Knowles said: “He doesn’t recall too much and fully accepts what is put forward. He desperately wants the relationship to continue. He has let himself down.
“He is having a hard time in prison. He is a young man and has a completely different side to him.”
The judge sentenced him to two months in prison despite the attempts of Keane’s lawyer to avoid jail time.
He then gave him an extra month on top as a result of the prior suspended sentence being violated.