I'd chew my agent out. Obviously they aren't experienced with foreclosure sales as 15 days is the long average (many banks only give 10 days) It's critical that any Buyer agent working with someone like yourself know this in advance and have everything lined up and ready to go.
Is the contract you received back the HUD addendum, typically the standard offer to purchase is used first, if your offer is accepted then a second bank or HUD addendum is sent to you for signature and this is where the 15 day period is listed. You sign it first and then it's returned to the bank to sign the 15 days begins from the time the Sellers signs off.
If this is already done, and you truly don't have time to get your inspections done for any reason, you've got two choices,get your agent to come up with the money that it's going to cost you to keep moving forward (good luck with that) or terminate your contract in writing immediately and either stop pursuing foreclosures which are rarely the deal buyers think they are, or come back with a new contract. HUD contract do allow for termination within the 15 day period and this will save you your earnest money deposit.
You've learned a very valuable lesson which is not all buyer brokers are the same and this is why it's critical to interview any broker/agent your considering using and ask them straight out the following:
How many years have you been a full time agent? (You want someone with at least 5 years of experience and 10 is better) How many transactions did you close last year/ (Don't work with anyone who closed less than 12 transactions in a year and again more is better.) If you are determined to by a foreclosure you need to find out how many foreclosure sales has the agent handled in the past couple of years, again you want someone who has handled at least half a dozen and again the more the better. Under no circumstances do you want to ever buy directly from the listing agent of foreclosure properties. Theses agents have the ethics of their masters; the banks who feed them these properties to list. They will cut your heart out with a dull spoon and could care less.
As someone with extensive experience with representing buyers and with foreclosure properties in specific; I will repeat myself yet again, Foreclosures are rarely the deal Buyers think they are. Out of 10 foreclosure sales 1 or 2 at best is really a deal, 6-7 are average deals at best after all the work is done and 1-2 are real money pits that will suck a buyer dry. They are inherently more risky to buy and first time homeowners should avoid them like the plague. There are many motivated Sellers in today's market and the deal you get can be as good or better and the risk you assume will be less.