Please help.

Let me tell you about my situation. I am nearly 27. I am married and have 4 children ages 9, 6, 2 and 18 months old. While I was unsure if I was completely done having children, I definitely knew that I wasn’t ready for one right now. I thought I’d tell-access when I turned 30 and see how I felt about having one more. I love love looooove being a mother and I love all of my beautiful daughters. It feels natural to have all of them in my life even at a younger age. Lately, there’s been some changes in our life. We recently moved from a higher paying job to be closer to family. We lived about two hours away for a while and during the birth and early months of my youngest life, I felt I needed to be near my mom/dad/in laws for extra support. So we’ve been back in my hometown for about a year now and my husband basically had to start his career over. We are currently living in a 2 bedroom condo with all 4 kids, basically just waiting for things to pick up. It’s been HARD. Our marriage has been put to the test. My patience is at an all time low. We are broke. And 3 days ago I found out I’m pregnant. Stupid me for being so naive and having no birth control. Stupid us for using the pull out method. And I am STRUGGLING. I’m struggling hard to come to a confident decision about what I want. I’ve never felt unsure about a pregnancy. I’ve never questioned it. And now I am. And it’s really hard. My husband is supportive of whatever I want. But he has also stated that he thinks we’d be able to turn things around and make it work. He’d have to find a job that makes 3 times what he’s making now. We need a new car, a new house. There have been moments where I feel positive... almost a little excited. But then there are moments where I think, “I really hope this is all a dream” or “god I don’t want to be pregnant- I can’t do this”. I feel guilt about adding another child to the mix when I struggle to divide my attention amongst the children I already have. I feel sad to take my baby’s ‘baby’ role away from her. I have so many emotions. I’ve never considered abortion.. but this time around I’m seriously considering it. It doesn’t help that my husband had to leave for a work trip the very next morning after we found out late at night. I’ve been sitting with this completely alone.. how do I make this decision?? I don’t know what to do.