I'm afraid I could not find your other 2 posts so will have to go just on this one.
You sound very stressed and really do need some outside help to help you straighten matters out.
Before I say anything else though I must point out you have done your exams, which in the anxious state you are in now is a big achievement, you also have time left to do your 40 hours.
I'd like to make a couple of suggestions. Being in a fog due to competing important demands can be a paralyzing sort of thing and I'd suggest you go see a GP in an extended consultation and say what has been happening and how you have been feeling - see what happens.
The other is to see Uni counseling services, they are used to students not getting through all the competing demands and will have suggestions as to which way to go, maybe even arrange a deferment or interview if necessary.
At the moment you seem to be concentrating on apologizing to the various people, which is understandable, however it may not be that all is lost with your main 140hr project, or the limpets.
Can I suggest after seeing counseling you consider writing thngs down and offering explanations that way, then take them there personally, so discussions can take place. Just emailing or posting would not be conducive to working things out.
There are some thngs you should know, I've been a uni educator for very many years and your situation is not uncommon, quite the reverse, and often it comes about though simple lack of experience, not knowing realistically what one is capable of. An important learning process.
The fact you sat your exams will count for a lot.
Good luck and please tell us how you get on