helloo! i need advice guys

whilst driving my mini countryman 4s in a slightly snowy road, i had a misadventure:

upon breaking, the abs got turned on ( driving speed 40 km/h) and wouldnt let go anymore, no matter how much i stepped on the break pedal, the abs kept running, but the car was not stopping mainly coz the pedal was getting stuck after any pressure on it.

the only alternative was to pound on the pedal, which i did until the on board computer displayed an error, at this point the braked started working again but without abs, and simultaniously had 3 warning light pop on my screen.

luckily the road was clear so i stoped the car with the help of the hand brake and turned it of. a couple minutes later, i turned on the car and started again and the car was working well.

i had the car checked on at the main dealership, and their response was that i needed snow tyres, and that i shouldn't had forcesd the breaks. ( it seems i should have crashed )

recap:
.there wasn't more than 2 cm of snow on the roads
.no ice
.abs failed

my car stats:
countryman all4 s
mileage: 15,000 km
tyres: pirelly, cinturato P7 . 17 inch mini cooper recommeded)

my questions:

has anyone experienced a similar event? or could anyone make sens of it?

 

the three lights are normally an ABS sensor trouble , unsure if you had a sensor issue that cleared