Your question is basically one of priorities, including what to allot for enjoying life. Your $2,600 per mouth should probably be enough to cover all your priorities including some fun money.
Here is a general account funding priority that usually works well for many people (when there is no HSA use):
1) Contribute to the work-based plans (401k, 403b, 457, TSP, etc.) enough to get the full employer match (the match is like free money, your best possible investment);
2) pay off high interest debt (a guaranteed high return, the next best thing to free money);
3) Contribute the maximum to an IRA, traditional or Roth (or backdoor Roth technique), depending on eligibility and personal circumstances (If the company plan offers good, low-cost funds, it may be preferable to contribute to the company plan before contributing to an IRA.);
4) Contribute the remainder of the maximum employee contribution to the work-based accounts; and
5) Contribute to a taxable investing account.
Please see the wiki article "Prioritizing investments"
. "If the company plan offers good, low-cost funds, it may be preferable to contribute to the company plan before contributing to an IRA. "
Some additional information would probably be useful in thinking through your priority question.
Contributing to your 401k, even without an employer match, would be a priority for your investing plans. It's important to make use of tax-advantaged accounts, if the funds offered are at all decent.
Could you please list the funds offered in the 401k, giving fund names, tickers and expense ratios? Please see this for format: "Asking Portfolio Questions"
What do you believe would be a reasonable amount to pay your parents per month for room and board while you still live at home?
In your locality about how much would a moderately priced evening out with your girlfriend cost, say dinner at a moderately priced restaurant and a movie?
If you buy lunch on a workday, about how much might that cost per day?
You have $5,000 in stocks. What firm is that account with, what are those stocks, and what is the capital gain/loss status of each of those stocks?
Do you have any short-term or intermediate-term financial goals in addition to paying off the student debt and starting your investing?
You can simply add this to your original post using the edit button (the pencil icon near the upper right corner of your post), it helps a lot if all of your information is in one place.
Summary of information provided so far.
Your salary is $45,000 per year.
You are paid $3,300 per month (about $39,600/yr), spend $700 per month, and have $2,600 a month ($31,200/yr) available for saving, investing, paying off debt, room and board to your parents, and fun.
The student debt of $30,000 is at about 5% interest.
There is no employer match offered in your 401k.
You have $20,000 savings (I have suggested contributing $5,500 of that to an IRA at Vanguard to start investing).
You also have $5,000 in stocks.