Ya, i believe Peter is still limited to one power at a time, thats why he said he came with Noah only to gain the other dudes ability because it would help him in his life-saving heroics ;P

If he had superspeed AND the superstrength he had before, the knife guy would have been toast since Peters knife swings would have been several times stronger than his, not to mention the kicks Peter landed on the knife fella would have seriously messed his insides up.