NL25 party; all-in flop semi-bluff w OESD

[ellipse_87]

Still finding my feet in NL, was hoping I could get some feedback on this flop play. Hand history is on another computer; here's how it went down roughly.

NOTE: I am aware that my pre-flop play was sub-standard.

Full-ring party 25NL. Very early, no reads. Both villains have me covered.

I'm in SB w T9s; EP raises to $1 big blind; MP calls. I raise to $3 trying to steal. Call, call.

Flop is 875 rainbow. I go all-in, roughly $25.

OK semi-bluff? Is it credible? Does the multi-way pot make me too vulnerable to a pocket pair 77 or better?

Thanks