Hi, I have a game tomorrow and i'm pitching, i was wondering if swimming, running, and riding a stationary bicycle TODAY, would be helpful for tomorrow

It might not make much of a difference. Now if you continually work on anerobic and aerobic, it can help. But hopefully you've already thrown a bullpen a day or two ago and are ready to take on this team tomorrow, as nothing should take the place of pitching from the mound. Though general fitness and specific fitness are helpful, along with mental toughness

Be ready tomorrow, have two plans going in:
A primary strategy and a secondary strategy.

Here's why,
When an athlete predicts and prepares for problems, tolerance and coping responses in performance will result (Averill, 1973; Orne, 1965). When developing strategies, apart from perparing what the pitcher prefers to do (like, start them off with a change up), athletes should also plan at least one other action in case the primary (preferred) behavior does not work.
The set of alternative or coping behaviors is called the "secondary strategy". A purpose of the secondary strategy would be to have "fall back" behaviors and to prepare for all possible distractions and problems. Effective results will be achieved if at least one alternate behavior for each primary behavior is prepared (Andrew, 1968; Meichenbaum & Turk, 1975).
Both primary and secondary (coping) behaviors should produce the same outcome.

Predicting and preparing for problems will produce better tolerance and coping responses in a game (Reid, 1973).

Also, no negative talk. All positive. "You're doing great, no one can beat us, I am going to pitch very accurately, etc..."