Commission based pay?

hey ladies as of today I received my job offer for Kay's jewelry! she wants to start me out at  $8.10 per hour plus commission. i'm six months pregnant right now and they are aware of that and are welcoming me with open arms which is a plus, but I'm just nervous that with that pay I'm not going to be able to make ends meet. can anyone give me some insight on what they think about this? i've never had commission based pay so I'm nervous about leaving my current job to take this one (right now I clean the cabinets for my mother and make decent money, it's just hard the farther along I get)