Ok...here goes.
Don't go back to the cot...get rid of it..let him help you get rid of it/dismantle it etc...even for just a few minutes so he can see what is happening.Honesty is best.
Make a book with him..something simple A4 paper stuck together, all about beds! Cut out catalogue pictures of beds to stick in it and pillows and duvets etc... print off a picture of a bed from the internet to colour in...or scribble on...doesn't matter!!!...type 'colouring in bed' into google images for the front cover...That sort of idea...write in big letters the word 'bed' underneath. Ok... that's done.
This is to give a positive association with the bed.
Now for a routine. This is going to be tough but stick with it. You will have seen this technique on TV masses of times but it works. I have been a nanny for 16years and it has never failed me. It won't fail you either but it needs complete focus and consistancy. You must not revert to what you did before no matter how tired you are...if you do, all of your good work is utterly useless...it may take a few days or a week or two. However long.never stop!
Teatime and last drink
Bathtime/ teethbrush. Quiet talking/ lowered tones..keep everything calm and serene.If necessary, bath him really early. It doesn't matter. It simply gives you longer to do things in a more controlled manner. Bathing an exhausted child who is tearful is a nightmare waiting to happen!
Warmed towel...cosy warmed pyjamas on radiator...last wee wee if potty training and then pj's/nightime nappy on...one cosy little boy!
Onto bed in dim room..Books already chosen earlier in the day. Tuck in and read quietly. At end of story time...(always stick with the same number of books however many 1,2,5,whatever!) Kiss goodnight...love you...light off and door shut.
Here you go!!!!!
Have a chair outside his door to sit on/ magazine...you'll need to make yourself comfy! When he starts to scream and yell....ignore. If he comes out of the door, take his hand and say Bedtime now and put him into bed...no kiss...not too much tucking in but with absolute serenity..no tense face or worried looks. He IS ok!
Door shut...sit on your chair and start again. Next time though and all the other times after, don't speak or look at him at all but don't be mean either...gentleness, take his hand/guide him back nicely. If he is kicking and screaming at you put him back into bed the nicest way you can...don't get cross and don't react. You will be ok and he IS ok. You are teaching him something new and showing him he is safe. This may go on for a few hours but it WILL lessen each night until it doesn't happen anymore.
IMPORTANT...If all goes quiet, leave him...do NOT sneak in. You can check him later on when he has been sleeping a while. If you sneak the door open and he is awake...all hell will let loose!
Now..all that said, you need to be happy with it all and thoroughly know what you are doing. Don't start something you feel you can't continue. Adjust the plan to suit you or ignore completely It is your choice as it is you who has got to put in all the hard work.
I wish you the very best and especially with the speech too. xx