BIG HUGS
I am very sorry. Multiple losses are extremely hard to bear.
I have also lost 4 piggies this year between January and August; one of them was only 3 years old (cancer).
However, I am still recovering from losing a staggering 22 piggies in the two years between 15th August 2021 and 15th August 2023; that has been nearly a piggy per month on average - only that it happened more in lumps with me losing 2-3 piggies in just a week about 5 times; a year ago just before Christmas two of them only a day apart in the wake of the first extreme cold spell (even though they are all indoors piggies) and I contracted Long Covid about halfway through, which hasn't helped.
I only had around 27 piggies at any time during this but I also have to mention that I have been extremely blessed that I didn't lose any piggies at all in the first 18 months of the pandemic but have then made up a with a vengeance since. The spell mirrors my biggest adoption spree the years around 2017. But it has been simply horrendous. I did go into grieving indigestion (i.e. I lost the ability to process) for about half a year between October and April this year, only to unexpectedly having to pts young Tegeirian in May... Occasionally the undigested bits come up in a hard lump; especially with a any new loss. This is also what you are currently experiencing.
Since my own piggy history goes back over half a centiry to my childhood piggies, I have had enough about small pets not being worth grieving for. But it is never about the species but about the quality of the bond. Those who say these things have never had pets themselves or they would understand how deeply we love - and how deeply we grieve for that precious love.
Be kind to yourself and give yourself time to work through it all; you cannot hurry on that process. Make sure that you do not get stuck in negative mind loops like feelings of guilt or being a bad owner. We humans are wired to reflect everything back onto ourselves, including coincidences and things we do not have any control over. We can only ever give our piggies a good and fulfilled life; we cannot choose when, what from and in what circumstances they pass - that is out of our control. Thankfully, piggies don't have a concept for an average life span; they measure their life in happy todays. As long as you have given them plenty of those, you have not failed them in any way and you are ahead, as far as they are concerned.
You may find the grieving guide I have written helpful. It contains a chapter on what we can positively do to help the grieving process on. You may also want to consider contacting one of the free Blue Cross (UK charity) pet bereavement platforms in order to talk it out of you; talking is the best thing you can do. Pet bereavement is now recognised as a mental health issue that can affect anybody and there is thankfully more trained help around these days.
Here are the links you may find helpful in making more sense of your strong and often unexpected emotions and thoughts:
Wiebke's Home Support Care Guides - Contents list and subforum link
Pet bereavement and pet loss
Please trust that it will get better again eventually. Grieving is also not just all bad. It is a time when our roots grow deeper and stronger in the process of coping with our pain. It makes us more understanding and empathetic towards the suffering of others and ultimately it makes us stronger when we come out at the other end. We still keep all those precious little memories and the richness our pets have brought into our lives is part of what makes us as persons; they will never be totally gone, unless you choose so. Grieving is the other side of love, but the love will endure.
I hope that this will help you.