This was instant matchpoints hand #10 (rotated), but our auction differed from one suggested in booklet. My question is what do the bids of pass, double, and three spades respectively mean. Is pass forcing?
At the table I doubled hoping partner would "do the right thing," but the consensus was this was just penalty and I should bid 3♠, which is fine. However, if instead the auction was
P-P-P-1♣
1♠-2♠-3♠-?
then what would my various bids mean (X versus pass versus 3NT)?

Help

P-P-P-1♣
1♥-2♥-3♥-?