need some info

ok i have no idea where to start on this lol so here goes

i am 28 and i am from the united kingdom
i have a Canadian wife of 4 years and 2 children (( one is mine and one is from her ex ))
i left canada 7 months ago after a phone call from family here in the uk telling me that my mother
is sick and she didnt have long left
so we where left in a hole
i ended up overstaying my visa by 4 months (1) lack of funds (2) as well as saving to come back here to see my mother we where also saving so my wife could move to kingston ontario due to the building we where in was not the best and i did not feel safe letting her stay there alone while there was drugs been sold all around her and my children

so at the end of my 4 month over stay we moved to Kingston
the day after i left for the uk
i did not get deported and i left of my own free will
but now once again i find my self in a hole
its 7 months on and now we have the money to do family class sponsorship
but we dont know if my over stay will cause a problem
also my daughters birthday is in 3 weeks .. and i would like to go back and spend 2 weeks with them
but i dont know if they will allow me to enter or not after my over stay

i have been to the office in london england
and all they said is that it is up to the person at POE
they might find me inadmissible due to the overstay or they might just want me to pay a bond
but i have no idea what to do ... its alot of money to fly out just to be told that i got to come back to the uk

i have looked all over the internet but have not been able to find any info
also my passport was not stamped at the uk (( woman in london england looked a little shocked at that )) .. but my passport has never been stamped when i have come back to the uk ... only in the us and canada

so i was wondering if someone could advise me on what my best move would be
and also if i am inadmissible how long would i be inadmissible for ... i have seen some sites that say a year and other that say 10 years but they all link to deported ... and i wasn't deported so i am lost

but thank you for any info