I’m so sorry to hear that you’ve lost your husband, and that the funeral was postponed due to a fire at the crematorium - it must have been a shock to get this news at the last minute when you would have been doing your best to mentally prepare for the event. It sounds as though it is a relief to have now been able to hold the ceremony.
I’m sorry also to hear that you now need to self-isolate and are not eligible for a test. That is just an added blow after everything else, and at a time when you are really in need of support.
I see that you are new to this Online Community, and I hope that it can help you a little to get through this period of isolation, and any other times when you might need it. You aren’t alone in your grief - there are many supportive users here who have also lost their husband or wife and will understand some of what you are going through. When you feel ready, you might find it helpful to start a new conversation in the Losing a Partner category, and share your story there - you should then get lots of supportive replies.