Oil pressure insufficient after flushing.

[Clueless]

A little while ago I had my car serviced and, amongst other things, the engine was flushed to remove carbon deposits. After that the oil pressure insufficient light started flashing. Is it possible that there was a connection between the flushing and the drop in oil pressure and what would be the best way to resolve the problem? It seems to be reasonably OK at low speeds but kicks in when I pick up speed. Also, would I be right in assuming that because the warning light is flashing rather than constant that this is a borderline case rather than a catastrophic drop in pressure? I'm a little concerned because I have continued to drive the car for sometime -
yes, I'm an idiot - and am worried by the possibility of additional damage. Any advice would be gratefully received.

[GrandadMonkey]

Has an original Peugeot oil filter been used? Pattern parts often result in low oil pressure.

Always use a genuine Peugeot oil filter on these cars.

[Capncol]

Sometimes the sludge and muck dislodged when flushing can get sucked into the oil pump pickup, which can block the gauze filter and oil filter, I would try another flush and oil and filter change, then if that doesn't sort it, take the sump off and clean the gauze.