What a tricky situation! Sorry to hear about this stress.
While your NI payments were short last year, I think previous years’ contributions also count, rather than the most recent one (especially if you’ve not claimed anything yet). You could also qualify for the means-tested version, which doesn’t take your NI contributions into account.
Universal Credit involves New Style Employment and Support Allowance, which will give you some support while you’re not working. If you don’t qualify for UC, contributions-based ESA is still available (though a bit of a headache to get, sometimes – you may need to speak to a few people to get the right forms for it!). If you qualify for one of these benefits, you could access additional help for your rent or primary residence mortgage payments (though this is more like a loan that must be repaid in 12 months, and won’t cover interest payments). You could also request a mortgage holiday on your mortgage to free up cash flow right now, if you need.
I feel for you on the chronic pain/fibro front – I’ve got the same, and it’s a real humdinger of an issue when you’re trying to work, isn’t it? However, if you have these problems and claim ESA, you could be eligible for the additional premiums for those unable to work due to ongoing chronic conditions. Under UC, this is around an extra £300 a month. It involves a Work Capability Assessment – which has been temporarily suspended due to distancing measures – but it does get backdated. If you apply, and they decide you’re eligible for the extra, it gets paid in a backdated lump sum, which could help you out in the future. You could also claim Personal Independence Payment, which isn’t means-tested and is available for those receiving disability benefits (i.e., ESA premiums) – even when you go back to work.
You mention you work for yourself – is your entire income from shares? If not, it could be worth furloughing yourself to claim on the Job Retention Scheme based on your usual salary (not that of your income protection payments). Alternatively, you could consider making yourself redundant – this would further your entitlement to benefits that may not be available while you’re technically employed.
When your baby is born, you’ll have access to additional benefits such as Child Benefit, which will help your cash flow.
I hope this is of some help! Good luck 🙂