Should I try to get a new car soon?

I have a 1996 Honda Odyssey with about 227k miles on it I mean it runs well it starts up quickly but the interior is pretty messed up and it's pretty slow as in I usually have to go 40mph in a 35 zone to keep up but I was thinking should I try to get a new car with less miles?

If you want

Sure

If your Odyssey is having a hard time going 40 mph, you're a danger to the public. Take it off the road.

You only mention the interior is messed up. Seat covers, or cleaning, use of floor mats, may help some of that. The speed issue is more about other drivers, not that there's something wrong with the car. You might get the tires and speedometer/odometer checked to make sure it is reading properly. Perhaps, you've put the wrong size tires on the car, causing it to read faster than you're really traveling or that others are really speeding in those 35 mph zones, which is more likely true.

Your engine and mech systems should have another 70,000 - 150,000 miles before it's ready to fully retire. You could start putting $100/week away toward the purchase of another car, which should provide a good head start or provide the full replacement cost within a few years, when it is finally ready to retire and be replaced. (100/wk=10,000 in 2years or 20,000 in 4 years) - it should last about 5-7 more years, if you really provide the proper TLC to keep fluids, brakes, rubber, replaced as needed.