Of course this is a huge decision and right now I'm sure you must feel very overwhelmed. Do you have a CPN/ psychologist/ anyone more neutral to discuss things with? Do you have any sense how many weeks you are right now? If you're still early on, you don't need to make this decision immediately - there may be a a bit of time to think still. You can even make appointments either way and then cancel them, if you did say now that you 'wanted a termination' so you could get an appointment, you have every right to change your mind right up until the last minute.
However, it obviously seems like that's not what you want, and unfortunately sometimes, no amount of rational pros/ cons lists can take away a gut feeling. Trying to interrogate your own thoughts may be worthwhile - for example, do you think if other people were more supportive of you making your own choice and your mum wasn't dismissing your feelings you'd feel the same? I'm not saying yes/no, but from my own experience of pushing back against parental views, I know it might make me dig further into a position. If you decided to continue, financial circumstances, housing, support networks and formal mental health support available to you will make a huge difference to how you manage. Without knowing these, no one can really give good advice apart from saying that it is your decision.
A positive story for you: I became pregnant in circumstances not dissimilar to yours. I was in the midst of a crisis, experiences SA and had taken several ODs in as many weeks and was habitually self harming. I'd been diagnosed with EUPD (and have since been diagnosed with ADHD - i suspect the EUPD was a misdiagnosis). So, my life was a bit of a mess. I spent a month trying to decide what to dom, but really I knew I was just trying to find a way to justify knowing that I wanted to keep it to people. Pregnancy was challenging and if you continue, you should prepare to accept that people will be expecting you to struggle and you may end with you some involvement from SS, perinatal mental health team. Don't fight it, accept whatever help you can get. Honestly, having my daughter was the best thing that could have happened to me, despite the challenges. After struggling for many years with my MH, I had such a clear sense of purpose, became involved with supporting other mums and am now a midwifery student.
Obviously this is just my experience. You know yourself. Pregnancy could be triggering for ED - nausea, vomiting etc. However, there is research suggesting that it can be a protective factor for some women. I still find the sensory overload of small children hard sometimes, but I'm much better at managing it. Good luck x