P reg punto, rad leaked now temp is over heating. got oil and water??

hello, My radiator leaked all over the petrol station yesterday. My lovely ex husband checked the oil and water. put oil in and refilled the water for me and all seemed well ish. This morning howver I went to go out and the temp just went up and up and beore I'd gone half a mile was in the red. I've parked and left my fiat P reg in a local car park and walked home, but desperayly need it sorted cos I've got to shuffle the kids round! Apologies for not being more mechanically detailed but I'm An engine phobic unless doing the oil, water etc checks. Any advice gratefully recieved.